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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 Starch particle Physicochemical properties Starch function Resistant starch Starch extraction
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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The characteristics of cerebral cortical oxygenation levels and functional connectivity under upper and lower limb exercise-induced fatigue
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作者 Feng Li Yajie Wang +3 位作者 Xinyi Wang Jiawei Bi Ye Luo Lingyan Huang 《Sports Medicine and Health Science》 2026年第1期61-69,共9页
This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fati... This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fatigue was induced using an upper limb ergometer or a lower limb ergometer,with the load increasing gradually each minute.fNIRS covering the prefrontal cortex and motor cortex were used to collect data during the resting state,both before and after fatigue induction.A two-way ANOVA was conducted to examine differences in oxyhemoglobin(HbO_(2))and functional connectivity before and after fatigue induction in both groups,with the significance level set at 0.05.Exercise-induced fatigue in both the upper and lower limbs leads to a significant decrease in cerebral cortical oxygenation levels.Upper limb fatigue leads to a significant reduction in functional connectivity,there were significant decreases in connectivity within the motor cortex,between the motor cortex and frontal regions,and between the right ventrolateral prefrontal cortex and other frontal regions.Conversely,no significant changes were observed before and after lower limb fatigue.Future studies should focus on examining the extent to which how changes in the cerebral cortex,induced by exercise fatigue,are linked to exercise-and/or performance-related outcomes. 展开更多
关键词 Brain functional connectivity Cerebral oxygenation level Exercise-induced fatigue functional near-infrared spectroscopy
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Functional genes associated with the occurrence of mycotoxins produced by Aspergillus in foods
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作者 Mei Gu Can Liu +4 位作者 Xiaofeng Yue Du Wang Xiaoqian Tang Qi Zhang Peiwu Li 《Journal of Integrative Agriculture》 2026年第2期585-601,共17页
Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural pro... Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural products,thereby endangering human health.Extensive studies on Aspergillus fungi have been conducted on growth and development,aflatoxin biosynthesis,and their interactions with environment.Here,we summarized a series of functional genes of the main Aspergillus fungi relative to toxins occurrence in foods,which revealed the signal transduction mechanisms of their involvement in growth and development,toxin production,and response to light,anticipating providing theoretical guidance on developing control and prevention technologies for mycotoxin contamination in agricultural products to ensure food safety. 展开更多
关键词 functional genes ASPERGILLUS AFLATOxIN DEVELOPMENT
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Periodontitis pathogen Porphyromonas gingivalis promotes chronic obstructive pulmonary disease via affecting neutrophils chemotaxis and function
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作者 Luyao Zhang Huan Tian +4 位作者 Yuanyuan Ma Jing Xu Chang Guo Zuomin Wang Jie Ma 《International Journal of Oral Science》 2026年第1期115-125,共11页
Chronic obstructive pulmonary disease(COPD),a disease responsible for early mortality worldwide,is well accepted to be associated with periodontitis epidemiologically.Although both of the diseases are the multi-microb... Chronic obstructive pulmonary disease(COPD),a disease responsible for early mortality worldwide,is well accepted to be associated with periodontitis epidemiologically.Although both of the diseases are the multi-microbial inflammatory disease,the precise underlying mechanisms by which periodontitis influences the progression of COPD remains largely unknown.Here,we established COPD accompanied with periodontitis mouse models and observed the pronounced progress in pulmonary symptoms and histopathology,cha racterized by poorer respiratory function,thicke ned bronchial walls,and increased neutrophils infiltration in lung tissue.Mechanistically,periodontitis pathogen Porphyromonas gingivalis(P.gingivalis)relocated in the lung through the respiratory tract and LPS from P.gingivalis promoted the secretion of chemokines CXCL2 and G-CSF of alveolar epithelial cells through NF-κB and p38 MAPK pathways to recruit neutrophils.Furthermore,exposure to P.gingivalis of infiltrated neutrophils released matrix metallopeptidase-8(MMP-8)and neutrophil elastase(NE),which aggravated airway inflammation and tissue damage.These findings indicated that periodontitis could exacerbate COPD via its pathogen P.gingivalis,which translocated in the lung and stimulated neutrophil chemotaxis and activation in the lung. 展开更多
关键词 neutrophils chemotaxis pulmonary symptoms HISTOPATHOLOGY PERIODONTITIS neutrophils function chronic obstructive pulmonary disease respiratory function chronic obstructive pulmonary disease copd
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Smart molecular design for functional cellulose gels and flexible devices
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作者 Zeshi Li Minxin Wang +4 位作者 Geyuan Jiang Jianhong Zhou Donghan Li Weihua Zhang Dawei Zhao 《Smart Molecules》 2026年第1期1-30,共30页
Cellulose,the dominant natural polymer on Earth,features a distinct molecular structure with extraordinary mechanical properties and tunable characteristics,making it attractive for gel systems.Although significant pr... Cellulose,the dominant natural polymer on Earth,features a distinct molecular structure with extraordinary mechanical properties and tunable characteristics,making it attractive for gel systems.Although significant progress has been made,challenges remain in fully leveraging their functional potential and broadening practical applications.This review systematically examines the properties of cellulose and cellulose gels,exploring novel reinforcement strategies—across molecular,supramolecular network,and macroscale structure levels—to enhance mechanical,electrical,and thermal performance,while coordinating these properties for practical implementations.These advancements are exemplified in emerging fields such as flexible robotics,electronic skins,flexible energy storage devices,and human-machine interaction systems.This article thoroughly investigates the fundamental characteristics,multi-scale design approaches,performance enhancement mechanisms,and cutting-edge implementations of cellulose-based gels across diverse domains.It provides a comprehensive overview of these advanced materials and offers strategic insights and recommendations for future research and innovation. 展开更多
关键词 CELLULOSE flexible electronics flexible robotics functional gels reinforcement design
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The effect of exercise rehabilitation on bone mineral density,muscle strength,and physical function outcomes in ACL ruptures:A randomized controlled clinical trial
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作者 Yue Wu Ruilan Dai +4 位作者 Yunan Zhou Wenqiang Yan Shuang Ren Xi Gong Yingfang Ao 《Sports Medicine and Health Science》 2026年第2期185-192,共8页
The purpose is to explore the effects of Exercise rehabilitation(ER)on bone mineral density(BMD)of the knee,muscle strength(MS),and physical function(PF)after ACL rupture.Finally,A total of 58 patients were randomized... The purpose is to explore the effects of Exercise rehabilitation(ER)on bone mineral density(BMD)of the knee,muscle strength(MS),and physical function(PF)after ACL rupture.Finally,A total of 58 patients were randomized into 2 groups(Control Group[CON]:conventional treatment,male=16,female=13,age=[31.63±8.01]years;Exercise rehabilitation group[ER]:6-week ER on CON basis,male=17,female=12,age=[31.26±7.07]years).At baseline and 6 weeks,the knee BMD was measured using DEXA,MS and PF measures were recorded by isokinetic strength test,IKDC,Lysholm,and VAS score.T-tests,analysis of variance(ANOVA),and Mann-Whitney tests were used for comparisons.The BMD outcomes:after a 6-week period,the BMD of the CON([1.47±0.24]g·cm^(-2))was significantly lower than that of the ER([1.65±0.37]g·cm^(-2))at lateral condyle of femur(LCF)(p=0.041).MS outcomes:at 6 weeks,the relative peak torque(RPT)of the quadriceps and hamstrings during concentric contractions in ER group were significantly higher than that in CON group(p<0.001,p=0.017).Similarly,during eccentric contractions in ER group,the RPT of the quadriceps and the H/Q ratio revealed significant variations from the CON group(p=0.033,p=0.043).PF outcomes:the IKDC,Lysholm,and VAS scores of the ER group were significantly improved compared to the CON group(p<0.001,p<0.001,p=0.002).The conclusion is that 6 weeks of ER intervention for patients with ACL rupture can effectively delay the decline of BMD in the LCF of the knee joint,and enhance the restoration of MS and PF.This provides guidance for clinical rehabilitation. 展开更多
关键词 Anterior cruciate ligament REHABILITATION Bone mineral density Joint function
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Correlation of ocular surface function with sleep quality,anxiety,and depression in patients with dry eye disease
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作者 Yi-Long Lin Hai-Hua Liu +2 位作者 Shu-Jin Chen Qi-Hua Wan Kai-Ping Zhang 《World Journal of Psychiatry》 2026年第1期256-266,共11页
BACKGROUND Dry eye disease(DED)is a multifactorial ocular surface disorder with rising prevalence.It is closely related to systemic health and psychological factors,such as sleep and mood disorders,which significantly... BACKGROUND Dry eye disease(DED)is a multifactorial ocular surface disorder with rising prevalence.It is closely related to systemic health and psychological factors,such as sleep and mood disorders,which significantly impact the quality of life of patients.AIM To explore the correlations between ocular surface function,sleep quality,and anxiety/depression in patients with DED.METHODS This was a cross-sectional investigative study that included 358 patients with DED between January 2022 and January 2025.Ocular surface was assessed using the ocular surface disease index(OSDI),tear film break-up time,fluorescein staining score,and Schirmer I test.The Pittsburgh Sleep Quality Index(PSQI),Self-Rating Anxiety Scale(SAS),and Self-Rating Depression Scale(SDS)were used to evaluate sleep quality and anxiety/depression levels.Correlation and linear regression analyses were used to explore the relationships.RESULTS The mean PSQI score of the patients was 9.94±2.18;the mean SAS score was 47.30±4.90,and the mean SDS score was 50.08±5.52.These suggested a prevalence of sleep and psychological abnormalities.There was a significant correlation between the indicators of ocular surface function(OSDI,tear film break-up time,fluorescein staining,and Schirmer I test)and PSQI,SAS,and SDS scores(P<0.05).Moreover,multiple regression revealed that age≥50 years(β=1.55,P=0.029),PSQI scores(β=0.58,P<0.001),SAS scores(β=0.17,P=0.017),and SDS scores(β=0.15,P=0.019)were independent predictors of the OSDI scores.CONCLUSION Ocular surface function in patients with DED is closely related to sleep quality and anxiety/depression,emphasizing the need for holistic clinical management. 展开更多
关键词 Dry eye disease Ocular surface function Sleep quality ANxIETY DEPRESSION
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Nitrogen functionalization of natural hydroxyl cellulose induces a LiF-rich interphase for lithium metal batteries
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作者 Jie Deng Ningxin Chen +5 位作者 Sida Xie Shan Liu Zichan Yuan Shuaiming He Shi Chen Zhaohui Wang 《Journal of Energy Chemistry》 2026年第2期37-47,I0003,共12页
Cellulose,the most abundant and renewable biopolymer,offers a sustainable and cost-effective solution for regulating lithium electrodeposition toward safer lithium metal batteries,thanks to its high nanofibrous struct... Cellulose,the most abundant and renewable biopolymer,offers a sustainable and cost-effective solution for regulating lithium electrodeposition toward safer lithium metal batteries,thanks to its high nanofibrous structure and intrinsic lithiophilic property.In this work,we introduce interface-engineered cellulose-based separators by converting intrinsic hydroxyl groups on cellulose nanofibers(CNFs)to nitrogen functionalities through a trace conducting polymer coating.Both experimental and theoretical results reveal that the nitrogen moieties disrupt the compact hydrogen bond network within hydroxyl cellulose,enabling multiple nitrogen-lithium interactions that enhance lithium ion transport.In addition to an extraordinary Li^(+)transference number of 0.86 and a high ionic conductivity of 1.1 mS cm^(-1),the nitrogen-functionalized CNF contributes to a uniform electric field and Li^(+)concentration distribution across the lithium metal surface.This facilitates the formation of a LiF-rich solid electrolyte interface and suppresses Li dendrite growth.Consequently,Li‖Li cells demonstrate stable plating/stripping cycles for approximately 3000 h at a current density of 1 mA cm^(-2) with a fixed capacity of 1 mAh cm^(-2),while maintaining a low overpotential of 15 mV.Our work provides valuable insights into the surface functionalization of natural biomass for advancing sustainable energy storage technologies. 展开更多
关键词 Cellulose nanofiber Nitrogen functionalization SEPARATOR Solid electrolyte interphase Lithium metal anodes
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Exploring the industrial potential of Moroccan oat varieties for functional food applications
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作者 Salma Touil Aouatif Benali +2 位作者 Ahmed Douaik Nadia Belahbib Nezha Saidi 《Grain & Oil Science and Technology》 2026年第1期42-52,共11页
Morocco's oat sector is shifting from forage to food,creating demand for varieties with proven processing performance.We profiled nine Moroccan oats(four parental lines,four interspecific derivatives,and one hull-... Morocco's oat sector is shifting from forage to food,creating demand for varieties with proven processing performance.We profiled nine Moroccan oats(four parental lines,four interspecific derivatives,and one hull-less diploid check)against the key drivers of functionality:β-glucan,hydration metrics(WAI,WSI,swelling power),interfacial metrics(foam capacity/stability,emulsion capacity/stability),and kernel geometry(thousand-kernel weight/width),using SEM to interpret microstructure.Varietal differences were pronounced and actionable.The A.sativa×A.magna derivative Hamdali showed fast wetting(low WAI),strong foaming(highest FS),and high emulsion capacity.These traits make it suitable for oat drinks and large,crack-free flakes.The A.sativa×A.murphyi descendants Al Fawze and Abtah exhibited restrained swelling(lower SP)and moderate WAI/WSI,favoring crisp snacks,biscuits,and pasta;Abtah additionally delivered high emulsion stability suitable for shelf-stable beverages.Amlal and Nezha offered balanced,steerable profiles.Linkingβ-glucan,hydration,and interfacial behavior to kernel traits provides a variety-to-application map for Moroccan oats.We recommend Hamdali/Niema for foamed beverages/flakes;Tissir/Soualem for porridges and thick beverages;Abtah for pasta and stable emulsions;Al Fawze for crisp snacks/biscuits. 展开更多
关键词 Moroccan oat cultivars Techno-functional traits functional food applications Grain microstructure Interspecific crosses
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Self-Activating Integrated Carbon-Based Air Cathodes With In Situ Oxygen Functionalization for Durable and High-Performance Metal-Air Batteries
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作者 Funing Bian Yuexi Chen +3 位作者 Hongfei Zhang Junfang Cheng Shulin Gao Sujuan Hu 《Carbon Energy》 2026年第1期176-186,共11页
Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal ... Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal additives or complex multilayer configurations.To tackle these issues,this study devised a self-activated integrated carbon-based air cathode.By integrating in situ catalytic site construction with structural optimization,the strategy not only induces the formation of oxygen functional groups(─C─OH,─C═O,─COOH),hierarchical pores,and uniformly distributed active sites,but also establishes a favorable electronic and mass-transport environment.Furthermore,the roll-pressing-based integrated design streamlines electrode construction,reinforces interfacial bonding,and significantly enhances mechanical stability.Density functional theory(DFT)calculations show that oxygen functional groups initiate hydrogen bonding interaction and promote charge enrichment,which improves the activity of the cathode and facilitates intermediate adsorption/desorption in oxygen reduction and evolution reactions processes.As a result,the integrated air cathode-based rechargeable zinc-air batteries(RZABs)achieve a high specific capacity of 811 mAh g^(-1).It also performs well in quasi-solid-state RZABs and silicon-air batteries systems across a wide temperature range,demonstrating strong adaptability and application potential.This study provides a scalable and cost-effective design strategy for high-performance carbon-based air cathodes,offering new insights into advancing durable and practical metal-air energy systems. 展开更多
关键词 integrated air cathode metal-air batteries ORR/OER oxygen functional group engineering SELF-ACTIVATION
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Extreme Attitude Prediction of Amphibious Vehicles Based on Improved Transformer Model and Extreme Loss Function
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作者 Qinghuai Zhang Boru Jia +3 位作者 Zhengdao Zhu Jianhua Xiang Yue Liu Mengwei Li 《哈尔滨工程大学学报(英文版)》 2026年第1期228-238,共11页
Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instabili... Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instability,occur frequently in both experimental and operational data.This infrequency causes events to be overlooked by existing prediction models,which lack the precision to accurately predict inclination attitudes in amphibious vehicles.To address this gap in predicting attitudes near extreme inclination points,this study introduces a novel loss function,termed generalized extreme value loss.Subsequently,a deep learning model for improved waterborne attitude prediction,termed iInformer,was developed using a Transformer-based approach.During the embedding phase,a text prototype is created based on the vehicle’s operation log data is constructed to help the model better understand the vehicle’s operating environment.Data segmentation techniques are used to highlight local data variation features.Furthermore,to mitigate issues related to poor convergence and slow training speeds caused by the extreme value loss function,a teacher forcing mechanism is integrated into the model,enhancing its convergence capabilities.Experimental results validate the effectiveness of the proposed method,demonstrating its ability to handle data imbalance challenges.Specifically,the model achieves over a 60%improvement in root mean square error under extreme value conditions,with significant improvements observed across additional metrics. 展开更多
关键词 Amphibious vehicle Attitude prediction Extreme value loss function Enhanced transformer architecture External information embedding
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Functional central nervous system regeneration:Challenges from axons to circuits
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作者 Apolline Delaunay Mickael Le Boulc’h +1 位作者 Stephane Belin Homaira Nawabi 《Neural Regeneration Research》 2026年第5期1983-1984,共2页
The mature central nervous system(CNS,composed of the brain,spinal cord,olfactory and optic nerves)is unable to regenerate spontaneously after an insult,both in the cases of neurodegenerative diseases(for example Alzh... The mature central nervous system(CNS,composed of the brain,spinal cord,olfactory and optic nerves)is unable to regenerate spontaneously after an insult,both in the cases of neurodegenerative diseases(for example Alzheimer's or Parkinson's disease)or traumatic injuries(such as spinal cord lesions).In the last 20 years,the field has made significant progress in unlocking axon regrowth. 展开更多
关键词 parkinsons disease unlocking axon regrowth neurodegenerative diseases central nervous system cnscomposed functional regeneration axon regrowth spinal cord lesions central nervous system
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Moderately large amplitude forced vibration of sandwich functionally graded auxetic beams:an analytical approach
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作者 F.M.NASREKANI H.EIPAKCHI 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期99-114,共16页
Sandwich functionally graded(FG)auxetic beams are extensively utilized in aerospace,automotive,and biomedical industries due to their excellent strength-toweight ratio,impact resistance,and tunable mechanical properti... Sandwich functionally graded(FG)auxetic beams are extensively utilized in aerospace,automotive,and biomedical industries due to their excellent strength-toweight ratio,impact resistance,and tunable mechanical properties.The integration of FG materials with auxetic structures enhances their adaptability in advanced engineering applications.However,understanding their dynamic behavior under external excitations is essential for optimal design and structural reliability.Nonlinear interactions in such structures pose significant challenges in vibration analysis,necessitating robust analytical methods.This study presents a closed-form solution for the nonlinear forced vibration analysis of sandwich FG auxetic beams,offering an accurate and efficient method for predicting their dynamic response.The beam consists of two FG face sheets with material properties varying through the thickness and a re-entrant honeycomb auxetic core with an adjustable Poisson's ratio.The governing nonlinear equations of motion are derived using the first-order shear deformation theory(FSDT),the modified Gibson model,and the von Kármán relations,formulated through Hamilton's principle.A closed-form solution is obtained via the Galerkin method and multiple-scale technique.The results demonstrate that FG layers enable control of the overweight and dynamic response amplitude,with positive power law indexes reducing weight.Comparisons with finite element results confirm the accuracy of the proposed formulation. 展开更多
关键词 functionally graded(FG)auxetic beam nonlinear forced vibration closedform solution multiple-scale method first-order shear deformation theory(FSDT)
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Topical administration of GLP-1 eyedrops improves retinal ganglion cell function by facilitating presynaptic GABA release in early experimental diabetes
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作者 Yu-Qi Shao Yong-Chen Wang +6 位作者 Lu Wang Hang-Ze Ruan Yun-Feng Liu Ti-Hui Zhang Shi-Jun Weng Xiong-Li Yang Yong-Mei Zhong 《Neural Regeneration Research》 2026年第2期800-810,共11页
Diabetic retinopathy is a prominent cause of blindness in adults,with early retinal ganglion cell loss contributing to visual dysfunction or blindness.In the brain,defects inγ-aminobutyric acid synaptic transmission ... Diabetic retinopathy is a prominent cause of blindness in adults,with early retinal ganglion cell loss contributing to visual dysfunction or blindness.In the brain,defects inγ-aminobutyric acid synaptic transmission are associated with pathophysiological and neurodegenerative disorders,whereas glucagon-like peptide-1 has demonstrated neuroprotective effects.However,it is not yet clear whether diabetes causes alterations in inhibitory input to retinal ganglion cells and whether and how glucagon-like peptide-1 protects against neurodegeneration in the diabetic retina through regulating inhibitory synaptic transmission to retinal ganglion cells.In the present study,we used the patch-clamp technique to recordγ-aminobutyric acid subtype A receptor-mediated miniature inhibitory postsynaptic currents in retinal ganglion cells from streptozotocin-induced diabetes model rats.We found that early diabetes(4 weeks of hyperglycemia)decreased the frequency of GABAergic miniature inhibitory postsynaptic currents in retinal ganglion cells without altering their amplitude,suggesting a reduction in the spontaneous release ofγ-aminobutyric acid to retinal ganglion cells.Topical administration of glucagon-like peptide-1 eyedrops over a period of 2 weeks effectively countered the hyperglycemia-induced downregulation of GABAergic mIPSC frequency,subsequently enhancing the survival of retinal ganglion cells.Concurrently,the protective effects of glucagon-like peptide-1 on retinal ganglion cells in diabetic rats were eliminated by topical administration of exendin-9-39,a specific glucagon-like peptide-1 receptor antagonist,or SR95531,a specific antagonist of theγ-aminobutyric acid subtype A receptor.Furthermore,extracellular perfusion of glucagon-like peptide-1 was found to elevate the frequencies of GABAergic miniature inhibitory postsynaptic currents in both ON-and OFF-type retinal ganglion cells.This elevation was shown to be mediated by activation of the phosphatidylinositol-phospholipase C/inositol 1,4,5-trisphosphate receptor/Ca2+/protein kinase C signaling pathway downstream of glucagon-like peptide-1 receptor activation.Moreover,multielectrode array recordings revealed that glucagon-like peptide-1 functionally augmented the photoresponses of ON-type retinal ganglion cells.Optomotor response tests demonstrated that diabetic rats exhibited reductions in visual acuity and contrast sensitivity that were significantly ameliorated by topical administration of glucagon-like peptide-1.These results suggest that glucagon-like peptide-1 facilitates the release ofγ-aminobutyric acid onto retinal ganglion cells through the activation of glucagon-like peptide-1 receptor,leading to the de-excitation of retinal ganglion cell circuits and the inhibition of excitotoxic processes associated with diabetic retinopathy.Collectively,our findings indicate that theγ-aminobutyric acid system has potential as a therapeutic target for mitigating early-stage diabetic retinopathy.Furthermore,the topical administration of glucagon-like peptide-1 eyedrops represents a non-invasive and effective treatment approach for managing early-stage diabetic retinopathy. 展开更多
关键词 diabetic retinopathy glucagon-like peptide-1 inhibitory synaptic transmission miniature inhibitory postsynaptic currents NEURODEGENERATION NEUROPROTECTION patch-clamp recording protein kinase C signaling pathway visual function
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Intermittent hypoxic perconditioning improves cognitive function in a mouse model of vascular cognitive impairment and dementia with comorbidities by recovering cerebral blood flow
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作者 Feiyang Jin Zhengming Tian +9 位作者 Yuying Guan Yuning Li Yakun Gu Mengyuan Guo Qianqian Shao Yingxia Liu Xiuhai Guo Zhenzhen Quan Jia Liu Xunming Ji 《Neural Regeneration Research》 2026年第6期2415-2424,共10页
Vascular cognitive impairment and dementia is a debilitating neurological disorder caused by chronic cerebral hypoperfusion,for which no effective causative treatments are currently available.Intermittent hypoxia has ... Vascular cognitive impairment and dementia is a debilitating neurological disorder caused by chronic cerebral hypoperfusion,for which no effective causative treatments are currently available.Intermittent hypoxia has been shown to enhance cerebral blood flow in mice,but its efficacy in a model of vascular cognitive impairment and dementia remains unclear.In this study,we established a mouse model of vascular cognitive impairment and dementia by bilateral carotid artery stenosis.Intermittent hypoxia was induced before and after this stenosis.We found that intermittent hypoxia increased cerebral blood flow,oxygen saturation,and microcirculation in the prefrontal cortex and hippocampus in the model mice,without causing neurovascular damage.Additionally,intermittent hypoxia significantly improved cognitive function in the mouse model of vascular cognitive impairment and dementia,with perconditioning showing greater efficacy than preconditioning.Improvements in cerebral microcirculation and blood flow were positively correlated with cognitive recovery.Even in a mouse model of vascular cognitive impairment and dementia with comorbidities induced by a high-fat,high-fructose diet,intermittent hypoxic perconditioning demonstrated protective effects on cognitive function.Proteomic analysis indicated that mitochondrial protection is a key mechanism,particularly through upregulating NDUFB8 expression and increasing the activity of mitochondrial complex I.These findings suggest that intermittent hypoxia is a potential non-invasive strategy for the prevention and treatment of vascular cognitive impairment and dementia. 展开更多
关键词 bilateral carotid artery stenosis cerebrovascular microcirculation chronic cerebral hypoperfusion cognitive function high fat-high fructose diet hippocampus intermittent hypoxia mitochondrial respiratory chain prefrontal cortex vascular cognitive impairment and dementia
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融合厚度信息的煤矸DE-XRT密度精准预测方法
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作者 郭永存 骆启生 +5 位作者 何磊 李德永 王爽 赵艳秋 刘宝莹 支亚 《煤炭科学技术》 北大核心 2026年第1期349-364,共16页
在煤矸智能分选领域,宽厚度-宽密度物料的密度预测受双能X射线透射物理机制、数据融合策略及物料复杂组分的综合影响,导致预测难度大、精度低,严重阻碍了煤矸智能光电分选技术发展和煤炭分质分级利用。为降低各因素影响,提高煤和矸石密... 在煤矸智能分选领域,宽厚度-宽密度物料的密度预测受双能X射线透射物理机制、数据融合策略及物料复杂组分的综合影响,导致预测难度大、精度低,严重阻碍了煤矸智能光电分选技术发展和煤炭分质分级利用。为降低各因素影响,提高煤和矸石密度预测精度,提出了一种基于虚拟厚度图像和改进密度公式的预测模型。该模型利用可变窗口式非线性平滑滤波降低夹矸现象的影响,以深度相机数据作为厚度基准对低能区图像灰度值进行校准,构建了可与双能X射线图像像素级对齐的虚拟厚度图像。探析了使用同一密度计算公式的影响,以各密度级煤矸计算结果的变化规律为依据对密度计算公式进行改进,建立了适用于煤和矸石的密度预测模型。此外,通过引入边界约束条件,进一步增加了模型的预测精度。通过与各种算法在不同密度级和厚度范围的煤矸数据集上进行对比测试,综合评估了所建立模型的性能。试验结果表明,该模型可以准确预测宽厚度-宽密度煤和矸石的密度。其中,对密度范围为1.30~1.80 g/cm^(3)、平均厚度范围为5~100 mm物料预测差值的均值MAE(Mean Absolute Error)和方差E-Var(Error Variance)最低分别为0.0539和0.0009;对密度>1.80 g/cm^(3)、平均厚度范围为5~100 mm物料预测差值的均值MAE和方差E-Var分别为0.2106和0.0332。相较于P值法、透射公式法、阿基米德法以及质量体积比值法,所建立模型可以在实现多目标同步测量的同时保持较高的精度和稳定性。此外,获得了准确性较高的电子密度图像,为后续的组分分析、质量质心计算、物料分布状态判断等关键环节提供数据参考。 展开更多
关键词 煤和矸石 密度预测 数据融合 双能x射线 深度相机
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基于深度相机与双能X射线双模态数据融合的煤矸识别和密度预测
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作者 郭永存 骆启生 +2 位作者 王爽 李德永 何磊 《煤炭学报》 北大核心 2026年第1期857-874,共18页
为削弱DE-XRT(Dual Energy X-Ray Transmission)系统的厚度效应,实现宽厚度范围内煤矸的精准识别和密度预测,深入总结了DE-XRT的成像原理,并在数据层面上融合了深度相机和DE-XRT。依据煤矸目标尺寸和区域相似性,针对性分区DE-XRT图像和... 为削弱DE-XRT(Dual Energy X-Ray Transmission)系统的厚度效应,实现宽厚度范围内煤矸的精准识别和密度预测,深入总结了DE-XRT的成像原理,并在数据层面上融合了深度相机和DE-XRT。依据煤矸目标尺寸和区域相似性,针对性分区DE-XRT图像和厚度图像,并通过将单像素扩展为多像素集合的方式,实现2类信息更加准确、高效地利用。进一步地,以各分区对应的X射线信息与厚度信息作为依据,利用射线能量衰减公式计算融合信息,并将各分区的融合信息统计为分块矩阵。通过分块矩阵和DE-XRT图像提取多维异构特征,结合Relief特征选择算法及GA(Genetic Algorithm)优化后的SVM(Support Vector Machine)分类器构建了一种适应性强的预识别模型。此外,通过对分块矩阵的变换计算和对大规模样本的统计分析,获取了各密度级煤的模糊区间,并构建了一种基于模糊区间的密度预测模型。该模型充分考虑了使用单一公式计算不同密度级煤的影响,通过建立模糊区间将煤密度的预测问题拆分成多个密度级的预测问题。同时,以待预测目标与区间下限的偏离度表征其与下限密度级的接近程度。试验结果表明:在处理煤密度范围为1.30~1.80 g/cm^(3)、矸石密度范围为>1.80 g/cm^(3)、平均厚度范围为5~100 mm的数据集时,预识别模型的精确率Pre和F_(1)分别为97.522%和0.962。相比现有X射线算法、灰度纹理法及深度学习算法,Pre、F_(1)分别至少提高6.433%和2.888%。密度预测模型的平均误差不超过5.882%,且46.993%的目标预测误差小于4%,93.233%的目标误差小于10%。所提模型可有效减少厚度效应对分选系统的影响,提高宽厚度范围内煤矸的识别和密度预测精度,为智能光电煤矸分选技术研发提供了理论依据。 展开更多
关键词 煤矸识别 密度预测 双能x射线 深度相机 数据融合
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不同强度X射线辐照下高气压SF6和空气放电特性研究
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作者 潘如政 陈皓伟 +2 位作者 章程 张国宝 杨为 《绝缘材料》 北大核心 2026年第1期110-118,共9页
采用X射线成像技术对大体积的电气设备进行可视化检测时,高能X射线是否会对其中的组合电器绝缘特性造成影响尚不明确。为研究X射线辐照对组合电器放电的作用规律,本文采用高能穿透X射线源,在六氟化硫(SF6)和空气气氛中测量沿面闪络电压... 采用X射线成像技术对大体积的电气设备进行可视化检测时,高能X射线是否会对其中的组合电器绝缘特性造成影响尚不明确。为研究X射线辐照对组合电器放电的作用规律,本文采用高能穿透X射线源,在六氟化硫(SF6)和空气气氛中测量沿面闪络电压和击穿电压。通过调整X射线的强度,将辐照前后和辐照时的数据进行对比。结果表明:在SF6气体中,X射线辐照时的沿面闪络电压比辐照前的沿面闪络电压平均提高10.6%,X射线辐照前的沿面闪络电压比辐照后的沿面闪络电压高1~2 kV;在空气中,50 kV和100 kV X射线辐照时的沿面闪络电压比辐照前的沿面闪络电压平均降低8.8%,225 kV X射线辐照时的闪络电压接近辐照前的闪络电压,X射线辐照前和辐照后的沿面闪络电压没有变化;在X射线辐照下,辐照前后和辐照时的间隙击穿电压均无变化,说明X射线辐照对于内部的间隙放电影响较小。 展开更多
关键词 x射线 SF6 沿面闪络 表面电荷消散 击穿电压
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二维大片径Ti_(3)C_(2)T_(x)薄膜的制备及其电磁屏蔽性能
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作者 夏斌 喻莉 +5 位作者 罗志娟 王众 周娅玲 杨帆 张剑桥 程诗慧 《功能材料》 北大核心 2026年第2期109-114,共6页
二维Ti_(3)C_(2)T_(x)具有特殊的微观层状结构和良好的物理化学性能,被视为新型高效的电磁屏蔽材料。Ti_(3)C_(2)T_(x)薄膜是通过二维纳米片堆叠制备,因此单个Ti_(3)C_(2)T_(x)纳米片的性能和薄膜中片层排列的有序性都决定了Ti_(3)C_(2)... 二维Ti_(3)C_(2)T_(x)具有特殊的微观层状结构和良好的物理化学性能,被视为新型高效的电磁屏蔽材料。Ti_(3)C_(2)T_(x)薄膜是通过二维纳米片堆叠制备,因此单个Ti_(3)C_(2)T_(x)纳米片的性能和薄膜中片层排列的有序性都决定了Ti_(3)C_(2)T_(x)薄膜的电磁屏蔽性能。基于差速离心的方法,筛选并制备了二维大片径的Ti_(3)C_(2)T_(x)薄膜。利用X射线衍射仪、透射电子显微镜和扫描电子显微镜对Ti_(3)C_(2)T_(x)的化学组成、晶体结构和微观形貌进行表征,利用四探针测试仪和矢量网络分析仪研究了Ti_(3)C_(2)T_(x)的电导率和电磁屏蔽性能。结果表明,大片径Ti_(3)C_(2)T_(x)纳米片在薄膜中呈现规则有序排列,且6μm以上片径Ti_(3)C_(2)T_(x)薄膜的电导率可达1.62×10^(5)S/m,是小片径薄膜的1.5倍,其电磁屏蔽性能最高可达64.8 dB。同时,在薄膜厚度为11μm时具有4.3×10^(6)dB/m的单位厚度电磁屏蔽效能。 展开更多
关键词 二维纳米材料 Ti_(3)C_(2)T_(x) 有序排列 电磁屏蔽 导电性
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