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Chitosan alleviates symptoms of Parkinson's disease by reducing acetate levels, which decreases inflammation and promotes repair of the intestinal barrier and blood–brain barrier
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作者 Yinying Wang Rongsha Chen +7 位作者 Guolin Shi Xinwei Huang Ke Li Ruohua Wang Xia Cao Zhongshan Yang Ninghui Zhao Jinyuan Yan 《Neural Regeneration Research》 2026年第1期377-391,共15页
Studies have shown that chitosan protects against neurodegenerative diseases. However, the precise mechanism remains poorly understood. In this study, we administered chitosan intragastrically to an MPTP-induced mouse... Studies have shown that chitosan protects against neurodegenerative diseases. However, the precise mechanism remains poorly understood. In this study, we administered chitosan intragastrically to an MPTP-induced mouse model of Parkinson's disease and found that it effectively reduced dopamine neuron injury, neurotransmitter dopamine release, and motor symptoms. These neuroprotective effects of chitosan were related to bacterial metabolites, specifically shortchain fatty acids, and chitosan administration altered intestinal microbial diversity and decreased short-chain fatty acid production in the gut. Furthermore, chitosan effectively reduced damage to the intestinal barrier and the blood–brain barrier. Finally, we demonstrated that chitosan improved intestinal barrier function and alleviated inflammation in both the peripheral nervous system and the central nervous system by reducing acetate levels. Based on these findings, we suggest a molecular mechanism by which chitosan decreases inflammation through reducing acetate levels and repairing the intestinal and blood–brain barriers, thereby alleviating symptoms of Parkinson's disease. 展开更多
关键词 ACETATE adenosine 5′-monophosphate-activated protein kinase blood–brain barrier CHITOSAN dopamine neurons INFLAMMATION intestinal barrier Parkinson's disease peroxisome proliferator-activated receptor delta short-chain fatty acids
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Blood-brain barrier disruption and neuroinflammation in the hippocampus of a cardiac arrest porcine model:Single-cell RNA sequencing analysis 被引量:1
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作者 Tangxing Jiang Yaning Li +11 位作者 Hehui Liu Yijun Sun Huidan Zhang Qirui Zhang Shuyao Tang Xu Niu Han Du Yinxia Yu Hongwei Yue Yunyun Guo Yuguo Chen Feng Xu 《Neural Regeneration Research》 2026年第2期742-755,共14页
Global brain ischemia and neurological deficit are consequences of cardiac arrest that lead to high mortality.Despite advancements in resuscitation science,our limited understanding of the cellular and molecular mecha... Global brain ischemia and neurological deficit are consequences of cardiac arrest that lead to high mortality.Despite advancements in resuscitation science,our limited understanding of the cellular and molecular mechanisms underlying post-cardiac arrest brain injury have hindered the development of effective neuroprotective strategies.Previous studies primarily focused on neuronal death,potentially overlooking the contributions of non-neuronal cells and intercellular communication to the pathophysiology of cardiac arrest-induced brain injury.To address these gaps,we hypothesized that single-cell transcriptomic analysis could uncover previously unidentified cellular subpopulations,altered cell communication networks,and novel molecular mechanisms involved in post-cardiac arrest brain injury.In this study,we performed a single-cell transcriptomic analysis of the hippocampus from pigs with ventricular fibrillation-induced cardiac arrest at 6 and 24 hours following the return of spontaneous circulation,and from sham control pigs.Sequencing results revealed changes in the proportions of different cell types,suggesting post-arrest disruption in the blood-brain barrier and infiltration of neutrophils.These results were validated through western blotting,quantitative reverse transcription-polymerase chain reaction,and immunofluorescence staining.We also identified and validated a unique subcluster of activated microglia with high expression of S100A8,which increased over time following cardiac arrest.This subcluster simultaneously exhibited significant M1/M2 polarization and expressed key functional genes related to chemokines and interleukins.Additionally,we revealed the post-cardiac arrest dysfunction of oligodendrocytes and the differentiation of oligodendrocyte precursor cells into oligodendrocytes.Cell communication analysis identified enhanced post-cardiac arrest communication between neutrophils and microglia that was mediated by neutrophil-derived resistin,driving pro-inflammatory microglial polarization.Our findings provide a comprehensive single-cell map of the post-cardiac arrest hippocampus,offering potential novel targets for neuroprotection and repair following cardiac arrest. 展开更多
关键词 Blood-brain barrier disruption cardiac arrest HIPPOCAMPUS microglia NEUROINFLAMMATION neuroprotection NEUTROPHIL oligodendrocyte dysfunction S100A8 single-cell RNA sequencing
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Interrelations between probiotics,gut microbiota,intestinal barrier,and immune response focusing on diarrhea in dairy calves
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作者 Munwar Ali Chang Xu +2 位作者 Qazal Hina Aoyun Li Kun Li 《Journal of Integrative Agriculture》 2026年第1期16-29,共14页
The interplay between gut microbiota and host health has attracted significant interest in the animal science community.Maintaining gut microbiota homeostasis by supplementing probiotics to treat clinical conditions l... The interplay between gut microbiota and host health has attracted significant interest in the animal science community.Maintaining gut microbiota homeostasis by supplementing probiotics to treat clinical conditions like calf diarrhea is an emerging area of research nowadays because of increased concerns regarding antimicrobial resistance(AMR)and drug residues in animal products.Probiotics reduce the incidence of calf diarrhea by increasing the gut microbiota diversity and richness with more commensal bacteria such as Lactobacillus and Bifidobacterium that produce antimicrobial compounds,as well as modulating the immune response by increasing cytokines,Interleukin-2(IL-2),IL-4,IL-6,IL-10,and reducing tumor necrosis factor-α(TNF-α),by increasing production of antibodies,especially immunoglobulin E(Ig E),also Ig G,differentiating naive Th lymphocytes(Tho)into Th1,hence stimulate innate immunity and prime the adaptive immune response.Specific probiotic strains of bacteria and yeast(Saccharomyces cerevisiae)derived probiotics maintain the integrity of the intestinal barrier.In this review,data are being organized to address the role of probiotics in treating calf diarrhea by modulating gut microbiota and stimulating an immune response against notorious pathogens,to present animal and veterinary scientists and nutritionists with a new concept to treat infectious diseases from the perspective of the gut microbiota,increasing animal health,performance,and welfare.In conclusion,health status and gut microbiome are strongly interlinked.Research data indicated a significant reduction in the incidence of diarrhea after probiotic administration.If interrelations between probiotics and existing gut microbiota are explored more quantitatively,novel antibiotic substitutes can emerge in the future. 展开更多
关键词 PROBIOTICS gut microbiota DIARRHEA CALVES intestinal barrier immune response
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Effect of“inert barrier layer”Ni on electron emission performance of dispenser cathode
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作者 Zheng Liu Yunfei Yang +4 位作者 Peng Liu Junhao Sun Hexiong Liu Yongfeng Cai Jinshu Wang 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期683-692,共10页
A novel trace nickel(Ni)doped tungsten(W)matrix with coated Ni on W grains was prepared by powder metallurgy method.The introduction of Ni can inhibit the reaction between W and barium-calcium aluminates(Ba-Ca alumina... A novel trace nickel(Ni)doped tungsten(W)matrix with coated Ni on W grains was prepared by powder metallurgy method.The introduction of Ni can inhibit the reaction between W and barium-calcium aluminates(Ba-Ca aluminates)during the impregnation process of the matrix.After cathode activation,the surface Ba:O molar ratio is 0.88:1.00,much higher than the Ba dispenser cathode without Ni doping.The XPS results of the cathode surface showed that the metallic Ba appeared on the activated cathode surface,forming dipoles with oxygen,and effectively reducing the cathode surface work function.The pulse electron emission current density at 1100℃_(b)(brightness temperature)was 18.26 A/cm^(2),and the calculated work function was 1.97 eV.It has a low evaporation rate and the accelerated lifetime test predict a lifetime of over 160000 h.First-principles calculations showed that the charge transfer and dipole moment in the NiW-BaO system were both increased compared to the Ba dispenser cathode,thus improving the emission performance of the Ni-W mixed matrix cathode. 展开更多
关键词 NICKEL inert barrier layer PASSIVATION EVAPORATION dispenser cathode
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Qualitative Research on the Current Implementation Status and Barriers of Nurses’Non-Pharmacological Prescription Authority
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作者 Ying Li Yulin Lu +3 位作者 Yanxia Shang Ling Huang Panpan Cui Pingxi Yang 《Journal of Clinical and Nursing Research》 2026年第1期331-337,共7页
Objective:To systematically review the current implementation status of nurses’non-pharmacological prescription authority and analyze the barriers encountered during its implementation in China,providing countermeasu... Objective:To systematically review the current implementation status of nurses’non-pharmacological prescription authority and analyze the barriers encountered during its implementation in China,providing countermeasures and references for promoting the standardized implementation of nurses’non-pharmacological prescription authority.Methods:A secondary analysis of literature was conducted to systematically search for domestic and international literature related to nurses’non-pharmacological prescription authority.Meta-analysis was performed on eligible literature to evaluate the implementation effects.Simultaneously,semi-structured in-depth interviews were conducted with healthcare workers,patients,and policymakers.Content analysis was used to organize the interview data and extract core issues and barriers.Results:A total of 46 international articles were included in the Meta-analysis,which revealed that the implementation of nurses’non-pharmacological prescription authority significantly improved patients’health management outcomes,enhanced healthcare service efficiency,and increased patient satisfaction.Conclusion:The implementation of nurses’non-pharmacological prescription authority has demonstrated significant positive effects.However,China faces multiple barriers in its advancement,necessitating efforts in optimizing policy systems,constructing collaborative models,strengthening professional skills training,and improving social awareness to guide the scientific and rational implementation of nurses’non-pharmacological prescription authority. 展开更多
关键词 Nurses Non-pharmacological prescription authority Implementation status barrier factors Qualitative research
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Tesla-Valve-Based Wind Barriers for Energy Dissipation and Aerodynamic Load Reduction on Trains
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作者 Bo Su Mwansa Chambalile +5 位作者 Shihao He Wan Sun Enyuan Zhang Tong Guo Jianming Hao Md.Mahbub Alam 《Fluid Dynamics & Materials Processing》 2026年第1期1-25,共25页
Predicting the precise impacts of climate change on extreme winds remains challenging,yet strong storms are widely expected to occur more frequently in a warming climate.Wind barriers are commonly used on bridges to r... Predicting the precise impacts of climate change on extreme winds remains challenging,yet strong storms are widely expected to occur more frequently in a warming climate.Wind barriers are commonly used on bridges to reduce aerodynamic loads on trains through blocking effects.This study develops a novel wind barrier based on Tesla valves,which not only blocks incoming flow but also dissipates mechanical energy through fluid collision.To demonstrate this energy-dissipation capability,a Tesla plate is placed in a circular duct to examine its influence on pressure drop.Experimental tests and numerical simulations comparing a Tesla channel and a straight channel of equal porosity show that the Tesla configuration produces a substantially higher pressure drop.Validated simulations are then used to conduct a parametric study to optimize the design.By varying the channel ratio,diversion angle,number of dissipation units,and porosity,velocity–pressure-drop relationships for different Tesla plates are obtained.The results show that larger channel ratios,larger diversion angles,and more dissipation units,combined with lower porosity,all increase pressure drop and thus enhance energy dissipation.Finally,the aerodynamic coefficients of a high-speed train on a bridge deck equipped with a Tesla-type barrier are evaluated and compared with those for a traditional straight-channel barrier.The Tesla-type barrier reduces the train’s lateral force coefficient to only 15%–25%of that produced by the traditional barrier,and it generates an additional stabilizing force that further improves running safety. 展开更多
关键词 Tesla plate wind barriers numerical simulation pressure drop aerodynamic coefficient
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Dietary supplementation with sodium isobutyrate enhances growth performance and colonic barrier function in weaned piglets via microbiota-metabolite-host interactions
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作者 Xiuyu Fang Zihan Chi +6 位作者 Zhengyi Wang Xinlin Wang Xingrui Qu Shuang Zhang Feng Gao Baoming Shi Xuan Zhao 《Journal of Animal Science and Biotechnology》 2026年第1期404-425,共22页
Background Weaning-induced diarrhoea and growth retardation in piglets are associated with impaired intestinal barrier function and decreased levels of colonic short-chain fatty acids(SCFAs).Although SCFA supplementat... Background Weaning-induced diarrhoea and growth retardation in piglets are associated with impaired intestinal barrier function and decreased levels of colonic short-chain fatty acids(SCFAs).Although SCFA supplementation has been proposed to mitigate these issues,the efficacy and optimal dosage of sodium isobutyrate remain unclear.Results We investigated the effects of sodium isobutyrate supplementation(500,1,000,2,000,and 4,000 mg/kg diet)on weaned piglets(Duroc×Landrace×Yorkshire,28 d of age;n=8).After a 28-d feeding trial,supplementation at 500–2,000 mg/kg significantly improved average daily gain and feed efficiency and reduced diarrhoea frequency,with maximal benefits observed at 1,000 mg/kg(P<0.0001).Additionally,500–1,000 mg/kg sodium isobutyrate supplementation increased the apparent digestibility of crude protein,organic matter,and crude fibre(P<0.05).Serum biochemical parameters were unaffected,although secretory immunoglobulin A(SIgA)levels significantly increased upon supplementation with 500–1,000 mg/kg(P<0.05).16S rRNA gene sequencing indicated that sodium isobutyrate increased the abundance of beneficial colonic microbiota.The 1,000 mg/kg group presented the most pronounced effect,with a significant increase of the relative abundance of Prevotella and the greatest improvement in SCFA concentrations(P<0.05).Metabolomics revealed elevated levels of colonic indole-3-lactic acid and 3-hydroxybutyrate upon supplementation with 1,000 mg/kg(P<0.05).Transcriptomic analyses indicated activation of protein digestion and absorption pathways,and PI3K-Akt signalling,marked by TSG-6 upregulation and the suppression of ISG15 and DDIT4 expression(P<0.05).Supplementation with 1,000 mg/kg was associated with improved intestinal barrier-related markers,including reduced serum D-lactate,diamine oxidase,and lipopolysaccharide levels,increased tight junction protein expression;activation of G protein-coupled receptors;and inhibition of TLR4/MyD88/NF-κB signalling(P<0.05),suggesting enhanced barrier function.Conclusions In conclusion,dietary supplementation with 1,000 mg/kg sodium isobutyrate was associated with improved intestinal morphology,reduced serum permeability,increased expression of tight junction proteins,and enhanced immune function in weaned piglets,suggesting enhanced colonic barrier function and providing dosage guidance and mechanistic insights for future applications. 展开更多
关键词 Colonic barrier function DIARRHOEA Intestinal microbiota Sodium isobutyrate Weaned piglets
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Roles of central nervous system resident and recruited macrophages in the brain barrier system
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作者 Ze Liu Teng Cheng +5 位作者 Hongtian Dong Dingya Sun Yan Wang Jiayan Li Zhongwang Yu Li Cao 《Neural Regeneration Research》 2026年第3期855-868,共14页
Macrophages in the brain barrier system include microglia in the brain parenchyma,border-associated macrophages at the brain’s borders,and recruited macrophages.They are responsible for neural development,maintenance... Macrophages in the brain barrier system include microglia in the brain parenchyma,border-associated macrophages at the brain’s borders,and recruited macrophages.They are responsible for neural development,maintenance of homeostasis,and orchestrating immune responses.With the rapid exploitation and development of new technologies,there is a deeper understanding of macrophages in the brain barrier system.Here we review the origin,development,important molecules,and functions of macrophages,mainly focusing on microglia and border-associated macrophages.We also highlight some advances in single-cell sequencing and significant cell markers.We anticipate that more advanced methods will emerge to study resident and recruited macrophages in the future,opening new horizons for neuroimmunology and related peripheral immune fields. 展开更多
关键词 border-associated macrophages brain barrier system cell markers development MICROGLIA NEUROIMMUNOLOGY recruited macrophages resident macrophages single-cell sequencing
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Advances in CNS drug delivery strategies to cross the blood-brain barrier
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作者 Guanlong Li Zhuoyan Li +6 位作者 Yan Sun Tiange Bu Shaochuan Chen Leixin Yang Zhi Li Wenyue Mao Yanpeng Jia 《Chinese Chemical Letters》 2026年第1期159-167,共9页
In recent years,development of strategies to treat central nervous system(CNS) diseases has attracted extensive attention.A major obstacle in this field is the blood-brain barrier(BBB),which significantly limits the e... In recent years,development of strategies to treat central nervous system(CNS) diseases has attracted extensive attention.A major obstacle in this field is the blood-brain barrier(BBB),which significantly limits the efficient delivery of therapeutic agents to the brain and hinders the treatment of CNS diseases.Overcoming the restrictive nature of the BBB has thus emerged as a key objective in CNS drug development.Nanomaterials have garnered growing interest due to their unique physicochemical properties and potential to traverse the BBB,enabling targeted drug delivery to brain tissue and improving therapeutic efficacy.In this review,we present current insights into the structure and function of the BBB and highlight a range of nanomaterial-based strategies for BBB penetration,including receptor-mediated transport(RMT),adsorptive-mediated transcytosis,reversible BBB disruption,and intranasal administration.Finally,we summarize recent advances in enhancing BBB permeability for CNS therapeutics and discuss persisting challenges,offering perspectives for future research in this field. 展开更多
关键词 Blood-brain barrier Brain target Central nervous system diseases Drug delivery NANOMATERIALS
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Beyond the barrier:Targeting blood-brain interactions for neuroprotection and repair
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作者 Anddre O.Valdivia Caroline Brandt Mark A.Petersen 《Neural Regeneration Research》 2026年第6期2341-2342,共2页
The central nervous system(CNS)does not function in isolation-it engages in continuous molecular dialogue with the vascular and immune systems.Traditionally,the blood-brain barrier(BBB)was portrayed solely as an imper... The central nervous system(CNS)does not function in isolation-it engages in continuous molecular dialogue with the vascular and immune systems.Traditionally,the blood-brain barrier(BBB)was portrayed solely as an impermeable wall,safeguarding the CNS by excluding blood-derived molecules and circulating cells.However,this view has evolved.The BBB is now recognized as a dynamic interface that selectively regulates the exchange of signals,cells. 展开更多
关键词 blood brain barrier dynamic interface REPAIR NEUROPROTECTION vascular system immune system vascular immune central nervous system cns
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Different roles of astrocytes in the blood–brain barrier during the acute and recovery phases of stroke
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作者 Jialin Cheng Yuxiao Zheng +8 位作者 Fafeng Cheng Chunyu Wang Jinhua Han Haojia Zhang Xin Lan Chuxin Zhang Xueqian Wang Qingguo Wang Changxiang Li 《Neural Regeneration Research》 2026年第4期1359-1372,共14页
Ischemic stroke,a frequently occurring form of stroke,is caused by obstruction of cerebral blood flow,which leads to ischemia,hypoxia,and necrosis of local brain tissue.After ischemic stroke,both astrocytes and the bl... Ischemic stroke,a frequently occurring form of stroke,is caused by obstruction of cerebral blood flow,which leads to ischemia,hypoxia,and necrosis of local brain tissue.After ischemic stroke,both astrocytes and the blood–brain barrier undergo morphological and functional transformations.However,the interplay between astrocytes and the blood–brain barrier has received less attention.This comprehensive review explores the physiological and pathological morphological and functional changes in astrocytes and the blood–brain barrier in ischemic stroke.Post-stroke,the structure of endothelial cells and peripheral cells undergoes alterations,causing disruption of the blood–brain barrier.This disruption allows various pro-inflammatory factors and chemokines to cross the blood–brain barrier.Simultaneously,astrocytes swell and primarily adopt two phenotypic states:A1 and A2,which exhibit different roles at different stages of ischemic stroke.During the acute phase,A1 reactive astrocytes secrete vascular endothelial growth factor,matrix metalloproteinases,lipid carrier protein-2,and other cytokines,exacerbating damage to endothelial cells and tight junctions.Conversely,A2 reactive astrocytes produce pentraxin 3,Sonic hedgehog,angiopoietin-1,and other protective factors for endothelial cells.Furthermore,astrocytes indirectly influence blood–brain barrier permeability through ferroptosis and exosomes.In the middle and late(recovery)stages of ischemic stroke,A1 and A2 astrocytes show different effects on glial scar formation.A1 astrocytes promote glial scar formation and inhibit axon growth via glial fibrillary acidic protein,chondroitin sulfate proteoglycans,and transforming growth factor-β.In contrast,A2 astrocytes facilitate axon growth through platelet-derived growth factor,playing a crucial role in vascular remodeling.Therefore,enhancing our understanding of the pathological changes and interactions between astrocytes and the blood–brain barrier is a vital therapeutic target for preventing further brain damage in acute stroke.These insights may pave the way for innovative therapeutic strategies for ischemic stroke. 展开更多
关键词 ASTROCYTES AXON blood–brain barrier cytokines endothelial cells glial scar ischemic stroke PHENOTYPE remodel vascular
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Photobiomodulation repairs the blood-spinal cord barrier in a mouse model of spinal cord injury
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作者 Yangguang Ma Yi Liu +6 位作者 Dongsheng Pan Jiawei Zhang Zhuowen Liang Yi Wang Xueyu Hu Zhe Wang Tan Ding 《Neural Regeneration Research》 2026年第6期2475-2484,共10页
The blood-spinal cord barrier is crucial for preserving homeostasis of the central nervous system.After spinal cord injury,autophagic flux within endothelial cells is disrupted,compromising the integrity of the blood-... The blood-spinal cord barrier is crucial for preserving homeostasis of the central nervous system.After spinal cord injury,autophagic flux within endothelial cells is disrupted,compromising the integrity of the blood-spinal cord barrier.This disruption facilitates extensive infiltration of inflammatory cells,resulting in exacerbated neuroinflammatory responses,neuronal death,and impaired neuronal regeneration.Previous research has demonstrated that photobiomodulation promotes the regeneration of damaged nerves following spinal cord injury by inhibiting the recruitment of inflammatory cells to the injured site and restoring neuronal mitochondrial function.However,the precise mechanisms by which photobiomodulation regulates neuroinflammation remain incompletely elucidated.In this study,we established a mouse model of spinal cord injury and assessed the effects of photobiomodulation treatment.Photobiomodulation effectively cleared damaged mitochondria from endothelial cells in mice,promoting recovery of hindlimb motor function.Using microvascular endothelial bEnd.3 cells subjected to oxygen-glucose deprivation,we found that the effects of photobiomodulation were mediated through activation of the PINK1/Parkin pathway.Additionally,photobiomodulation reduced mitochondrial oxidative stress levels and increased the expression of tight junction proteins within the blood-spinal cord barrier.Our findings suggest that photobiomodulation activates mitochondrial autophagy in endothelial cells through the PINK1/Parkin pathway,thereby promoting repair of the blood-spinal cord barrier following spinal cord injury. 展开更多
关键词 autophagy blood-spinal cord barrier endothelial cell mitochondria neuroinflammatory PHOTOBIOMODULATION PTEN-induced kinase 1 repair spinal cord injury tight junction
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Dynamic behavior of steel post/wood panel railway noise barriers under aerodynamic loads induced by high-speed trains
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作者 Dongyun Liu Chao Wang +3 位作者 Jaime Gonzalez-Libreros Andréas Andersson Lennart Elfgren Gabriel Sas 《Railway Engineering Science》 2026年第1期55-84,共30页
Railway noise barriers are an essential piece of infrastructure for reducing noise propagation.However,these barriers experience aerodynamic loads generated by high-speed trains,leading to dynamic effects that may com... Railway noise barriers are an essential piece of infrastructure for reducing noise propagation.However,these barriers experience aerodynamic loads generated by high-speed trains,leading to dynamic effects that may compromise their fatigue capacity.The most common structural design for railway noise barriers consists of vertical configurations of posts and panels.However,there have been few dynamic analyses of steel post/wood panel noise barriers under train-induced aerodynamic loads.This study used dynamic finite element analysis to assess the dynamic behavior of such noise barriers.Analysis of a 40-m-long noise barrier model and a triangular simplified load model,the latter of which effectively represented the detailed aerodynamic load,were first used to establish the model and input of the moving load during dynamic simulation.Then,the effects of different parameters on the dynamic response of the noise barrier were evaluated,including the damping ratio,the profile of the steel post,the span length of the panel,the barrier height,and the train speed.Gray relational analysis indicated that barrier height exhibited the highest correlations with the dynamic responses,followed by train speed,post profile,span length,and damping ratio.A reduction in the natural frequency and an increase in the train speed result in a higher peak response and more pronounced fluctuations between the nose and tail waves.The dynamic amplification factor(DAF)was found to be related to both the natural frequency and train speed.A model was proposed showing that the DAF significantly increases as the square of the natural frequency decreases and the cube of the train speed rises. 展开更多
关键词 Aerodynamic load Dynamic amplification factor Dynamic behavior Finite element analysis High-speed train Railway noise barrier
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Link between blood-brain barrier disruption and microglial activation
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作者 Arjun Sapkota Sebok K.Halder Richard Milner 《Neural Regeneration Research》 2026年第6期2317-2318,共2页
Cells of the central nervous system(CNS)are privileged in lying behind the blood-brain barrier(BBB).Unlike blood vessels in other organs,CNS blood vessels are unique in displaying high electrical resistance and low pe... Cells of the central nervous system(CNS)are privileged in lying behind the blood-brain barrier(BBB).Unlike blood vessels in other organs,CNS blood vessels are unique in displaying high electrical resistance and low permeability.With this unique structure and function,the BBB prevents potentially harmful blood components such as serum proteins,inflammatory cytokines,and inflammatory leukocytes from entering the hallowed space of the CNS and wreaking havoc.In addition to these“tightness”properties,the BBB has an array of specialized transporters designed to import essential nutrients. 展开更多
关键词 blood brain barrier microglial activation inflammatory leukocytes central nervous system unique structure blood vessels central nervous system cns serum proteinsinflammatory
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Research Progress on Bio-Based Biodegradable Barrier Materials
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作者 Kezheng Gao Shuaifei Li +1 位作者 Qingyuan Niu Xiaojing Zhang 《Journal of Renewable Materials》 2025年第12期2309-2353,共45页
The current global shortage of oil resources and the pollution problems caused by traditional barrier materials urgently require the search for new substitutes.Biodegradable bio-based barrier materials possess the cha... The current global shortage of oil resources and the pollution problems caused by traditional barrier materials urgently require the search for new substitutes.Biodegradable bio-based barrier materials possess the characteristics of being renewable,environmentally friendly,and having excellent barrier properties.They have become an important choice in fields such as food packaging,agricultural film covering,and medical protection.This review systematically analyzes the design and research of this type of material,classifying biobased and biodegradable barrier materials based on the sources of raw materials and synthesis pathways.It also provides a detailed introduction to the latest research progress of biobased and biodegradable barrier materials,discussing the synthesis methods and improvement measures of their barrier properties.Subsequently,it analyzes the related technologies for enhancing the barrier properties of biobased and biodegradable barrier materials,and finally looks forward to the directions that future research should focus on,promoting the transition of biobased and biodegradable barrier materials from the laboratory to industrial applications. 展开更多
关键词 Bio-based materials BIODEGRADABLE barrier material barrier performance enhance barrier measures
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Neutrophils disrupt the intestinal barrier via IL-22/TGF-β/Mmp9 axis in the zebrafish model of inflammatory bowel disease 被引量:1
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作者 Peixian Huang Yiqing Yang +3 位作者 Junwei Lian Tao Yu Gaofei Li Yiyue Zhang 《Journal of Genetics and Genomics》 2025年第7期962-965,共4页
Inflammatory bowel disease(IBD)comprises a heterogeneous group of chronic inflammatory conditions of the intestine.Current therapeutic strategies primarily focus on maintaining remission and mitigating the secondary e... Inflammatory bowel disease(IBD)comprises a heterogeneous group of chronic inflammatory conditions of the intestine.Current therapeutic strategies primarily focus on maintaining remission and mitigating the secondary effects rather than reversing its pathogenic mechanisms(Jeong et al.,2019).The pathogenesis of IBD involves intestinal barrier dysfunction,tissue damage,and dysregulated innate and adaptive immune responses(de Souza et al.,2017).Elevated neutrophil activity has been reported in IBD(Danne et al.,2024),yet the precise roles and mechanisms of neutrophils in disease progression remain to be elucidated. 展开更多
关键词 intestinal barrier dysfunctiontissue inflammatory bowel disease ibd comprises inflammatory conditions dysregulated innate adaptive immune responses de mitigating secondary effects intestinal barrier IL NEUTROPHILS
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基于“天河二号”聚合通信卸载特性的MPI_Barrier优化
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作者 朱琦 戴艺 +5 位作者 彭晋韬 谢旻 梁崇山 刘鹏 杨博 刘杰 《计算机工程与科学》 北大核心 2025年第3期400-411,共12页
Barrier作为消息传递接口MPI程序的基本操作,是确保程序正确执行的重要机制之一。目前已有的Barrier实现方案主要存在2个缺陷:首先,节点间同步存在大量冗余的数据路径传输开销;其次,节点内同步存在大量缓存失效的情况。为解决这些性能限... Barrier作为消息传递接口MPI程序的基本操作,是确保程序正确执行的重要机制之一。目前已有的Barrier实现方案主要存在2个缺陷:首先,节点间同步存在大量冗余的数据路径传输开销;其次,节点内同步存在大量缓存失效的情况。为解决这些性能限制,针对“天河二号”定制网络TH-Express聚合通信卸载特性,提出了基于GLEX NIC的Barrier加速和共享内存标志位重排列2种优化技术,有效减少了节点间同步开销,提高了节点内基于共享内存的同步效率。基于上述优化方法,重新设计了MPI_Barrier算法,并将其集成到MPI通信库中,并在国家超级计算长沙中心通过运行微基准测试程序和实际应用程序对所提优化方法进行性能测试,规模达到7168个节点。实验结果表明,优化后的MPI_Barrier集合操作获得了1.3~14.5倍的加速,并在应用级真实负载评测中,性能提升高达54%。 展开更多
关键词 MPI barrier 大规模并行应用 NIC聚合通信卸载
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Beyond wrecking a wall:revisiting the concept of blood–brain barrier breakdown in ischemic stroke 被引量:3
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作者 Julia Castillo-González Elena González-Rey 《Neural Regeneration Research》 SCIE CAS 2025年第7期1944-1956,共13页
The blood–brain barrier constitutes a dynamic and interactive boundary separating the central nervous system and the peripheral circulation.It tightly modulates the ion transport and nutrient influx,while restricting... The blood–brain barrier constitutes a dynamic and interactive boundary separating the central nervous system and the peripheral circulation.It tightly modulates the ion transport and nutrient influx,while restricting the entry of harmful factors,and selectively limiting the migration of immune cells,thereby maintaining brain homeostasis.Despite the well-established association between blood–brain barrier disruption and most neurodegenerative/neuroinflammatory diseases,much remains unknown about the factors influencing its physiology and the mechanisms underlying its breakdown.Moreover,the role of blood–brain barrier breakdown in the translational failure underlying therapies for brain disorders is just starting to be understood.This review aims to revisit this concept of“blood–brain barrier breakdown,”delving into the most controversial aspects,prevalent challenges,and knowledge gaps concerning the lack of blood–brain barrier integrity.By moving beyond the oversimplistic dichotomy of an“open”/“bad”or a“closed”/“good”barrier,our objective is to provide a more comprehensive insight into blood–brain barrier dynamics,to identify novel targets and/or therapeutic approaches aimed at mitigating blood–brain barrier dysfunction.Furthermore,in this review,we advocate for considering the diverse time-and location-dependent alterations in the blood–brain barrier,which go beyond tight-junction disruption or brain endothelial cell breakdown,illustrated through the dynamics of ischemic stroke as a case study.Through this exploration,we seek to underscore the complexity of blood–brain barrier dysfunction and its implications for the pathogenesis and therapy of brain diseases. 展开更多
关键词 blood–brain barrier disruption drug delivery ischemic stroke NEUROINFLAMMATION tight-junctions
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Human-induced pluripotent stem cell-derived neural stem cell exosomes improve blood-brain barrier function after intracerebral hemorrhage by activating astrocytes via PI3K/AKT/MCP-1 axis 被引量:3
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作者 Conglin Wang Fangyuan Cheng +9 位作者 Zhaoli Han Bo Yan Pan Liao Zhenyu Yin Xintong Ge Dai Li Rongrong Zhong Qiang Liu Fanglian Chen Ping Lei 《Neural Regeneration Research》 SCIE CAS 2025年第2期518-532,共15页
Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor prognosis.Human-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)... Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor prognosis.Human-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system diseases.In this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying mechanism.Our results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leukocyte infiltration in a mouse model of intracerebral hemorrhage.Additionally,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory microenvironment.RNA sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier integrity.Treatment with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these effects.In summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes. 展开更多
关键词 AKT ASTROCYTE blood-brain barrier cerebral edema EXOSOMES human-induced pluripotent stem cells intracerebral hemorrhage neural stem cells NEUROINFLAMMATION PI3K
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Poly(lactic acid)/Poly(butylene adipate-co-terephthalate)films with simultaneous high oxygen barrier and fast degradation properties 被引量:1
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作者 Mengjing Yang Yuxi Mao +4 位作者 Penghui Zhang Jie Li Zeming Tong Zhenguo Liu Yanhui Chen 《Green Energy & Environment》 SCIE EI CAS 2025年第1期1-10,共10页
Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are stil... Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are still insufficient for high-barrier packaging applications.In this study,oxygen scavenger hydroxyl-terminated polybutadiene(HTPB)and cobalt salt catalyst were incorporated into the PLA/poly(butylene adipate-co-terephthalate)(PLA/PBAT),followed by melting extrusion and three-layer co-extrusion blown film process to prepare the composite films.The oxygen permeability coefficient of the composite film combined with 6 wt%oxygen scavenger and 0.4 wt%catalyst was decreased significantly from 377.00 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1) to 0.98 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1),showing a remarkable enhancement of 384.69 times compared with the PLA/PBAT composite film.Meanwhile,the degradation behavior of the composite film was also accelerated,exhibiting a mass loss of nearly 60%of the original mass after seven days of degradation in an alkaline environment,whereas PLA/PBAT composite film only showed a mass loss of 32%.This work has successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior,which has great potential for high-demanding green chemistry packaging industries,including food,agricultural,and military packaging. 展开更多
关键词 barrier property Oxygen scavenging Blow molding Eco-packaging Degradable composite film
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