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Pro-resolving lipid mediator reduces amyloid-β42–induced gene expression in human monocyte–derived microglia
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作者 Ying Wang Xiang Zhang +6 位作者 Henrik Biverstål Nicolas GBazan Shuai Tan Nailin li Makiko Ohshima Marianne Schultzberg xiaofei li 《Neural Regeneration Research》 SCIE CAS 2025年第3期873-886,共14页
Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment o... Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment of Alzheimer's disease to prevent/stop inflammation and combat disease pathology. Therefore, it is important to clarify whether they counteract the expression of genes and proteins induced by amyloid-β. With this objective, we analyzed the relevance of human monocyte–derived microglia for in vitro modeling of neuroinflammation and its resolution in the context of Alzheimer's disease and investigated the pro-resolving bioactivity of maresin 1 on amyloid-β42–induced Alzheimer's disease–like inflammation. Analysis of RNA-sequencing data and secreted proteins in supernatants from the monocyte-derived microglia showed that the monocyte-derived microglia resembled Alzheimer's disease–like neuroinflammation in human brain microglia after incubation with amyloid-β42. Maresin 1 restored homeostasis by down-regulating inflammatory pathway related gene expression induced by amyloid-β42 in monocyte-derived microglia, protection of maresin 1 against the effects of amyloid-β42 is mediated by a re-balancing of inflammatory transcriptional networks in which modulation of gene transcription in the nuclear factor-kappa B pathway plays a major part. We pinpointed molecular targets that are associated with both neuroinflammation in Alzheimer's disease and therapeutic targets by maresin 1. In conclusion, monocyte-derived microglia represent a relevant in vitro microglial model for studies on Alzheimer's disease-like inflammation and drug response for individual patients. Maresin 1 ameliorates amyloid-β42–induced changes in several genes of importance in Alzheimer's disease, highlighting its potential as a therapeutic target for Alzheimer's disease. 展开更多
关键词 Alzheimer's disease amyloid-β maresin MICROGLIA MONOCYTE NEUROINFLAMMATION resolution RNA-sequencing specialized pro-resolving lipid mediator
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Light-absorbing impurities on Keqikaer Glacier in western Tien Shan: concentrations and potential impact on albedo reduction 被引量:4
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作者 YuLan Zhang ShiChang Kang +11 位作者 Min Xu Michael Sprenger TanGuang Gao ZhiYuan Cong Chaoliu li JunMing Guo ZhiQiang Xu Yang li Gang li xiaofei li YaJun liu HaiDong Han 《Research in Cold and Arid Regions》 CSCD 2017年第2期97-111,共15页
Light-absorbing impurities on glaciers are important factors that influence glacial surface albedo and accelerate glacier melt. In this study, the quantity of light-absorbing impurities on Keqikaer Glacier in western ... Light-absorbing impurities on glaciers are important factors that influence glacial surface albedo and accelerate glacier melt. In this study, the quantity of light-absorbing impurities on Keqikaer Glacier in western Tien Shan, Central Asia, was measured. We found that the average concentrations of black carbon was 2,180 ng/g, with a range from 250 ng/g to more than 10,000 ng/g. The average concentrations of organic carbon and mineral dust were 1,738 ng/g and 194 μg/g, respectively. Based on simulations performed with the Snow Ice Aerosol Radiative model simulations, black carbon and dust are responsible for approximately 64% and 9%, respectively, of the albedo reduction, and are associated with instantaneous radiative forcing of 323.18 W/m2(ranging from 142.16 to 619.25 W/m2) and 24.05 W/m2(ranging from 0.15 to69.77 W/m2), respectively. For different scenarios, the albedo and radiative forcing effect of black carbon is considerably greater than that of dust. The estimated radiative forcing at Keqikaer Glacier is higher than most similar values estimated by previous studies on the Tibetan Plateau, perhaps as a result of black carbon enrichment by melt scavenging. Light-absorbing impurities deposited on Keqikaer Glacier appear to mainly originate from central Asia, Siberia, western China(including the Taklimakan Desert) and parts of South Asia in summer, and from the Middle East and Central Asia in winter.A footprint analysis indicates that a large fraction(>60%) of the black carbon contributions on Keqikaer Glacier comes from anthropogenic sources. These results provide a scientific basis for regional mitigation efforts to reduce black carbon. 展开更多
关键词 light-absorbing IMPURITIES black carbon mineral dust GLACIER SNOW ALBEDO Tien Shan
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Effects of weeding and fertilization on soil biology and biochemical processes and tree growth in a mixed stand of Dalbergia odorifera and Santalum album 被引量:2
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作者 Peng Zhang xiaofei li +3 位作者 Shiyu Xue Zhiyi Cui Daping Xu Zengjiang Yang 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2633-2644,共12页
In southern China,the eucalyptus plantation industry has been severely restricted by government policy over concerns on negative environmental impacts.In its place,large-scale plantations of high-value tropical tree s... In southern China,the eucalyptus plantation industry has been severely restricted by government policy over concerns on negative environmental impacts.In its place,large-scale plantations of high-value tropical tree species such as nitrogen-fixing Dalbergia odorifera and hemiparasite Santalum album have been widely cultivated including in mixed-species plantations.However,despite their poor growth,little information is available on suitable silvicultural practices of these plantations.Therefore,we subjected an 8-year-old mixed stand of D.odorifera and S.album to weeding,fertilization,weeding+fertilization,or no(CK)treatments and measured soil microbial biomass,respiration,nutrients,nitrogen mineralization and leaching and tree growth and litter production.Weeding and fertilization decreased microbial biomass but increased soil respiration,inhibited mineralization,had not effect on leaching of soil nitrogen,and improved the nutrient status of plantation soil.All practices improved the growth of D.odorifera.In the mixed plantation,fertilization increased litter production and nutrient content,but weeding and weeding+fertilization decreased growth of S.album and litter production in mixed plantation because weeding decreased the number of S.album haustoria in underground plant roots.In conclusion,fertilization is recommended;however,weeding-related practices are inappropriate for D.odorifera and S.album mixed plantations.These conclusions have important implications for managing other parasite or mixed-species plantations. 展开更多
关键词 Plantation practices Microbial biomass Soil respiration MINERALIZATION LEACHING HEMIPARASITE
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GROWTH AND DISTORTION THEOREMS FOR ALMOST STARLIKE MAPPINGS OF COMPLEX ORDER λ 被引量:3
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作者 xiaofei ZHANG Jin LU xiaofei li 《Acta Mathematica Scientia》 SCIE CSCD 2018年第3期769-777,共9页
In this article, the sharp growth theorem for almost starlike mappings of complex order λ is given firstly. Secondly, distortion theorem along a unit direction is also established as the application of the growth the... In this article, the sharp growth theorem for almost starlike mappings of complex order λ is given firstly. Secondly, distortion theorem along a unit direction is also established as the application of the growth theorem. In particular, using our results can reduce to some well-known results. 展开更多
关键词 Distortion theorem convex mapping Schwarz lemma at the boundary
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Enhancing direct-path relative transfer function using deep neural network for robust sound source localization 被引量:1
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作者 Bing Yang Runwei Ding +2 位作者 Yutong Ban xiaofei li Hong liu 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第3期446-454,共9页
This article proposes a deep neural network(DNN)-based direct-path relative transfer function(DP-RTF)enhancement method for robust direction of arrival(DOA)estimation in noisy and reverberant environments.The DP-RTF r... This article proposes a deep neural network(DNN)-based direct-path relative transfer function(DP-RTF)enhancement method for robust direction of arrival(DOA)estimation in noisy and reverberant environments.The DP-RTF refers to the ratio between the directpath acoustic transfer functions of the two microphone channels.First,the complex-value DP-RTF is decomposed into the inter-channel intensity difference,and sinusoidal functions of the inter-channel phase difference in the time-frequency domain.Then,the decomposed DP-RTF features from a series of temporal context frames are utilized to train a DNN model,which maps the DP-RTF features contaminated by noise and reverberation to the clean ones,and meanwhile provides a time-frequency(TF)weight to indicate the reliability of the mapping.The DP-RTF enhancement network can help to enhance the DP-RTF against noise and reverberation.Finally,the DOA of a sound source can be estimated by integrating the weighted matching between the enhanced DP-RTF features and the DP-RTF templates.Experimental results on simulated data show the superiority of the proposed DP-RTF enhancement network for estimating the DOA of the sound source in the environments with various levels of noise and reverberation. 展开更多
关键词 network SOUND TRANSFER
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Protection of Compatibility of Saikosapon d and Baicalin on Carbon Tetrachloride Injured L-02 Cells Based on TLR4-NFκB Signaling Pathway
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作者 Min li Yiwen WANG +2 位作者 xiaofei li Jing li Bin WANG 《Medicinal Plant》 CAS 2018年第2期61-64,共4页
[Objectives] To study the protection of compatibility of Saikosapon d and Baicalin on carbon tetrachloride( CCl_4) injured L-02 cells. [Methods] Normal human hepatocyte cell line L-02 cells were cultured in vitro,and ... [Objectives] To study the protection of compatibility of Saikosapon d and Baicalin on carbon tetrachloride( CCl_4) injured L-02 cells. [Methods] Normal human hepatocyte cell line L-02 cells were cultured in vitro,and CCl_4 was used to induce hepatocellular injury. Interventions were carried out with Saikosaponin d and Baicalin at different dosage. The proliferation of L-02 cells in each group was determined by methylthiazolyl tetrazolium( MTT) assay; the levels of AST and ALT in the culture supernatants were detected by enzyme-linked immunosorbent assay( ELISA); the expressions of TLR4 and NFκBp65 proteins in each group were determined by immunohistochemistry.[Results] In the CCl_4 injured group,the proliferation of L-02 cells was significantly declined,the levels of AST and ALT in cell culture medium were significantly increased,and the expressions of TLR4 and NFκBp65 in L-02 cells were increased; after the intervention of Saikosaponin d and Baicalin,1. 75 μg/mL group and 1. 5 μg/mL group had an effect of promoting the proliferation of L-02 cells and could reduce the levels of AST and ALT in the cell culture medium,and TLR4 and NFκBp65 proteins in L-02 cells also had a certain inhibitory effect. [Conclusions] The compatibility of Saikosapon d and Baicalin has a certain protective effect on CCl_4 injured L-02 cells. The protection mechanism may be related with its down-regulating TLR4-NFκB signaling pathway and reducing the inflammation. 展开更多
关键词 Saikosapon d and Baicalin L-02 cells Carbon tetrachloride(CCl4) TLR4 NFΚB
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Application of Blockchain Technology in Optimizing Resource Allocation Efficiency
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作者 Jiaming li Yihan XU +2 位作者 li'nan JIN Nuoya liN xiaofei li 《Asian Agricultural Research》 2022年第7期19-21,共3页
Based on the existing literature,this paper analyzed and explored the factors that affect the efficiency of resource allocation,and evaluated the current situation of resource allocation in various fields.It is found ... Based on the existing literature,this paper analyzed and explored the factors that affect the efficiency of resource allocation,and evaluated the current situation of resource allocation in various fields.It is found that with the emergence of the new pattern of China’s economic development,the economic growth rate has slowed down,and the method of large-scale production driving economic growth is no longer applicable to the current economic situation.Nowadays,when structural transformation and upgrading have entered a new stage,to achieve the optimization of resource allocation efficiency,it is necessary to start from three aspects:improving information transparency,upgrading industrial structure,and planning government intervention.Through the adaptation analysis of blockchain technology and the existing problems in optimizing resource allocation efficiency,it explored the feasibility of blockchain technology to optimize resource allocation efficiency,and promote economical,efficient and high-quality development. 展开更多
关键词 Resource allocation EFFICIENCY Blockchain technology High-quality economic development APPLICATION
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Literature Review on the Impact of Blockchain Technology on Resource Allocation Efficiency
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作者 Nuoya liN li'nan JIN +2 位作者 Jiaming li xiaofei li Yihan XU 《Asian Agricultural Research》 2022年第6期18-20,共3页
With the rapid development of Internet technology,the importance of blockchain technology has become increasingly prominent.Faced with this situation,extensive research has been carried out at home and abroad.Through ... With the rapid development of Internet technology,the importance of blockchain technology has become increasingly prominent.Faced with this situation,extensive research has been carried out at home and abroad.Through the analysis of relevant literature on blockchain in recent years,it is found that there are many research results of blockchain technology in medical care,finance,education,etc.,but its application in the field of resource allocation efficiency is rare.From the existing studies on the influencing factors of resource allocation efficiency in China,it is found that there are significant differences in resource allocation efficiency between China and some developed countries or between various provinces and cities of China. 展开更多
关键词 Blockchain Resource allocation efficiency Influencing factors Literature review
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Effect of slope position on leaf and fine root C,N and P stoichiometry and rhizosphere soil properties in Tectona grandis plantations
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作者 Qingqing Zhang Zaizhi Zhou +4 位作者 Weiwei Zhao Guihua Huang Gaofeng liu xiaofei li Junduo Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1997-2009,共13页
Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation... Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation of these elements in trees and rhizosphere soils.Here we analyzed the C,N,P content and stoichiometry in leaves,fine roots and rhizosphere soils of trees on the upper and lower slopes of a 12-year-old teak plantation.The Kraft classification system of tree status was used to sample dominant,subdominant and mean trees at each slope position.The results showed that the C,N and P contents in leaves were higher than in fine roots and rhizosphere soils.The lowest C/N,C/P and N/P ratios were found in rhizosphere soils,and the C/N and C/P ratios in fine roots were higher than in leaves.Nutrient accumulation in leaves,fine roots and rhizosphere soils were significantly influenced by slope position and tree class with their interaction mainly showing a greater effect on rhizosphere soils.Leaf C content and C/N ratio,fine root C and P contents,and C/N and C/P ratios all increased distinctly with declining slope position.The contents of organic matter(SOM),ammonium(NH4+-N),nitrate-nitrogen(NO3--N)and available potassium(AK)in rhizosphere soils were mainly enriched on upper slopes,but exchange calcium(ECa),available phosphorus(AP),and pH were relatively lower.Variations in the C,N and P stoichiometries in trees were mainly attributed to the differences in rhizosphere soil properties.N and P contents showed significant positive linear relationships between leaf and rhizosphere soil,and C content negative linear correlation among leaves,fine roots and rhizosphere soils.Chemical properties of rhizosphere soils,particularly C/N and NH4+-N,had significant effects on the leaf nutrients in trees on the upper slope.Correspondingly,rhizosphere soil properties mainly influenced fine root nutrients on the lower slope,and soil AK was the major influencing factor.Overall,these results offer new insights for the sustainability and management of teak plantations in hilly areas. 展开更多
关键词 Tectona grandis Stoichiometric ratio Rhizosphere soil Dominant trees Nutrient accumulation
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Dissolved organic carbon fractionation in wet deposition and its potential impact on radiative forcing in the central Tibetan Plateau
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作者 ZhaoFu Hu Chaoliu li +5 位作者 ShiChang Kang xiaofei li Chao Zhang Fangping Yan XiaoBo He PengFei Chen 《Research in Cold and Arid Regions》 CSCD 2023年第4期171-178,共8页
As an important component of carbonaceous matters,dissolved organic carbon(DOC)can absorb and scatter the solar radiation at ultraviolet and blue wavelengths.The wet deposition process has great impact on the con-cent... As an important component of carbonaceous matters,dissolved organic carbon(DOC)can absorb and scatter the solar radiation at ultraviolet and blue wavelengths.The wet deposition process has great impact on the con-centration and light absorption ability of precipitation DOC,affecting the climatic effect caused by DOC in the atmosphere.In this study,light absorption and fluorescence characteristics of precipitation DOC was investigated in the central Tibetan Plateau(TP).The results showed that the mean DOC concentration and mass absorption cross-section measured at 365 nm(MAC_(365)) in Tanggula(TGL)station were 0.59±0.42 mg/L and 0.37±0.19 m^(2)/g,respectively,while both values showed much higher volatilities than those of aerosols.DOC concentrations had significant negative correlation with the precipitation amount,while MAC_(365) values increase with the precipitation amount in TGL station.Therefore,DOC with high light-absorbing ability was preferred to be retained in the atmosphere during wet deposition.In this study,precipitation DOC contained three fluorescent components(one humic-like component and two tyrosine-like components)mainly from local biomass burning sources.DOC concentration showed a negative relationship with MAC_(365) value in TGL station.The wet deposition of DOC with low light-absorbing ability can reduce the strong negative radiative forcing caused by secondary organic aerosol due to high proportion of DOC in secondary organic carbon.Similar phenomenon was also found in Nam Co,Lulang and Everest stations of previous study,which may have a potential impact on radiative forcing in the atmosphere of TP. 展开更多
关键词 Tibetan Plateau Wet deposition Dissolved organic carbon Light absorption ability Fluorescence characteristics
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Vision‐audio fusion SLAM in dynamic environments
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作者 Tianwei Zhang Huayan Zhang xiaofei li 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1364-1373,共10页
Moving humans,agents,and subjects bring many challenges to robot self‐localisation and environment perception.To adapt to dynamic environments,SLAM researchers typically apply several deep learning image segmentation... Moving humans,agents,and subjects bring many challenges to robot self‐localisation and environment perception.To adapt to dynamic environments,SLAM researchers typically apply several deep learning image segmentation models to eliminate these moving obstacles.However,these moving obstacle segmentation methods cost too much computation resource for the onboard processing of mobile robots.In the current industrial environment,mobile robot collaboration scenario,the noise of mobile robots could be easily found by on‐board audio‐sensing processors and the direction of sound sources can be effectively acquired by sound source estimation algorithms,but the distance estimation of sound sources is difficult.However,in the field of visual perception,the 3D structure information of the scene is relatively easy to obtain,but the recognition and segmentation of moving objects is more difficult.To address these problems,a novel vision‐audio fusion method that combines sound source localisation methods with a visual SLAM scheme is proposed,thereby eliminating the effect of dynamic obstacles on multi‐agent systems.Several heterogeneous robots experiments in different dynamic scenes indicate very stable self‐localisation and environment reconstruction performance of our method. 展开更多
关键词 dynamic environment intelligent robots sensor fusion
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Vascular restoration through local delivery of angiogenic factors stimulates bone regeneration in critical size defects
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作者 liang Fang Zhongting liu +9 位作者 Cuicui Wang Meng Shi Yonghua He Aiwu Lu xiaofei li Tiandao li Donghui Zhu Bo Zhang Jianjun Guan Jie Shen 《Bioactive Materials》 SCIE CSCD 2024年第6期580-594,共15页
Critical size bone defects represent a significant challenge worldwide,often leading to persistent pain and physical disability that profoundly impact patients’quality of life and mental well-being.To address the int... Critical size bone defects represent a significant challenge worldwide,often leading to persistent pain and physical disability that profoundly impact patients’quality of life and mental well-being.To address the intricate and complex repair processes involved in these defects,we performed single-cell RNA sequencing and revealed notable shifts in cellular populations within regenerative tissue.Specifically,we observed a decrease in progenitor lineage cells and endothelial cells,coupled with an increase in fibrotic lineage cells and pro-inflammatory cells within regenerative tissue.Furthermore,our analysis of differentially expressed genes and associated signaling pathway at the single-cell level highlighted impaired angiogenesis as a central pathway in critical size bone defects,notably influenced by reduction of Spp1 and Cxcl12 expression.This deficiency was particularly pronounced in progenitor lineage cells and myeloid lineage cells,underscoring its significance in the regeneration process.In response to these findings,we developed an innovative approach to enhance bone regeneration in critical size bone defects.Our fabrication process involves the integration of electrospun PCL fibers with electrosprayed PLGA microspheres carrying Spp1 and Cxcl12.This design allows for the gradual release of Spp1 and Cxcl12 in vitro and in vivo.To evaluate the efficacy of our approach,we locally applied PCL scaffolds loaded with Spp1 and Cxcl12 in a murine model of critical size bone defects.Our results demonstrated restored angiogenesis,accelerated bone regeneration,alleviated pain responses and improved mobility in treated mice. 展开更多
关键词 Critical size bone defects ANGIOGENESIS Spp1 CXCL12 Polycaprolactone scaffold
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Topological pseudospin switcher:Mechanism and acoustic realization
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作者 Jia-He Chen Yiyin Chen +11 位作者 Yaoqieyu Song Yongxu Xu Xinrong li Jingsong Wang Jiawei He Jiaxu Qu Zheng li xiaofei li Wenqiang lin Jiannan Chen Caixing Fu Zhi Hong Hang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2024年第5期46-53,共8页
The control of the pseudospin of sound wave has attracted increasing attention in recent years.Utilizing the finite-size effect of topological acoustics,we successfully construct an H-shaped acoustic topological pseud... The control of the pseudospin of sound wave has attracted increasing attention in recent years.Utilizing the finite-size effect of topological acoustics,we successfully construct an H-shaped acoustic topological pseudospin switcher that sound wave energy can be easily switched through different passages.The interesting phenomenon of pseudospin flipping is numerically and experimentally demonstrated.A quantitative interference theory is proposed that the constructive and destructive interference of pseudospin states leads to pseudospin flipping and preserving in multiple frequencies.We verify the key parameters of the design,including the length of the passage and its interface state dispersion,and the theory can be extended to other topology acoustics and photonics systems.Moreover,the tunable topological sonic crystal we use provides adjustable convenience to pseudospin switcher design.The pseudospin switching behavior offers an efficient method to control the acoustic topological edge state transport,which has great potential in versatile applications,such as integrated acoustics,acoustic security,and information processing. 展开更多
关键词 TOPOLOGICAL ACOUSTICS REALIZATION
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紫檀芪抗肿瘤作用机制研究进展 被引量:4
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作者 张晓雁 张娇 +6 位作者 徐丽群 马志强 狄守印 高原 李小飞 闫小龙 张红梅 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第12期931-936,共6页
紫檀芪(3,5-二甲氧基-4’-羟基二苯乙烯)是一种主要存在于蓝莓、葡萄和花榈木中的多酚类化合物。已有的研究发现紫檀芪具有抗肺癌、乳腺癌、胃癌、结肠癌等多种肿瘤的抗癌作用。其作用机制涉及调控影响多种肿瘤生物学特性。此外,紫檀芪... 紫檀芪(3,5-二甲氧基-4’-羟基二苯乙烯)是一种主要存在于蓝莓、葡萄和花榈木中的多酚类化合物。已有的研究发现紫檀芪具有抗肺癌、乳腺癌、胃癌、结肠癌等多种肿瘤的抗癌作用。其作用机制涉及调控影响多种肿瘤生物学特性。此外,紫檀芪具有比白藜芦醇更高的生物利用度和生物活性,其抗肿瘤作用和机制值得深入探讨和研究。 展开更多
关键词 紫檀芪 肿瘤 凋亡 增殖 侵袭
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The development of blood-retinal barrier during the interaction of astrocytes with vascular wall cells 被引量:6
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作者 Huanling Yao Tianshi Wang +3 位作者 Jiexin Deng Ding liu xiaofei li Jinbo Deng 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第10期1047-1054,共8页
Astrocytes are intimately involved in the formation and development of retinal vessels. Astrocyte dysfunction is a major cause of blood-retinal barrier injury and other retinal vascular diseases. In this study, the de... Astrocytes are intimately involved in the formation and development of retinal vessels. Astrocyte dysfunction is a major cause of blood-retinal barrier injury and other retinal vascular diseases. In this study, the development of the retinal vascular system and the formation of the blood-ret-inal barrier in mice were investigated using immunolfuorescence staining, gelatin-ink perfusion, and transmission electron microscopy. The results showed that the retinal vascular system of mice develops from the optic disc after birth, and radiates out gradually to cover the entire retina, taking the papilla optica as the center. First, the superifcial vasculature is formed on the inner retinal layer;then, the vasculature extends into the inner and outer edges of the retinal inner nuclear layer, forming the deep vasculature that is parallel to the superifcial vasculature. The blood-retinal barrier is mainly composed of endothelium, basal lamina and the end-feet of astrocytes, which become mature during mouse development. Initially, the naive endothelial cells were immature with few organelles and many microvilli. The basal lamina was uniform in thickness, and the glial end-feet surrounded the outer basal lamina incompletely. In the end, the blood-retinal barrier matures with smooth endothelia connected through tight junctions, rela-tively thin and even basal lamina, and relatively thin glial cell end-feet. These ifndings indicate that the development of the vasculature in the retina follows the rules of“center to periphery”and“superifcial layer to deep layers”. Its development and maturation are spatially and tempo-rally consistent with the functional performance of retinal neurons and photosensitivity. The blood-retinal barrier gradually becomes mature via the process of interactions between astro-cytes and blood vessel cells. 展开更多
关键词 nerve regeneration RETINA growth development blood vessels blood-retinal barrier ASTROCYTES IMMUNOFLUORESCENCE ULTRASTRUCTURE mouse collagen IV glial fibrillary acidic protein NSFC grant neural regeneration
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Piezo1 channel activation in response to mechanobiological acoustic radiation force in osteoblastic cells 被引量:15
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作者 Guangdao Zhang xiaofei li +1 位作者 lin Wu Yi-Xian Qin 《Bone Research》 SCIE CAS CSCD 2021年第2期223-232,共10页
Mechanobiological stimuli,such as low-intensity pulsed ultrasound(LIPUS),have been shown to promote bone regeneration and fresh fracture repair,but the fundamental biophysical mechanisms involved remain elusive.Here,w... Mechanobiological stimuli,such as low-intensity pulsed ultrasound(LIPUS),have been shown to promote bone regeneration and fresh fracture repair,but the fundamental biophysical mechanisms involved remain elusive.Here,we propose that a mechanosensitive ion channel of Piezo1 plays a pivotal role in the noninvasive ultrasound-induced mechanical transduction pathway to trigger downstream cellular signal processes.This study aims to investigate the expression and role of Piezo1 in MC3T3-E1 cells after LIPUS treatment.Immunofluorescence analysis shows that Piezo1 was present on MC3T3-E1 cells and could be ablated by shRNA transfection.MC3T3-E1 cell migration and proliferation were significantly increased by LIPUS stimulation,and knockdown of Piezo1 restricted the increase in cell migration and proliferation.After labeling with Fluo-8,MC3T3-E1 cells exhibited fluorescence intensity traces with several high peaks compared with the baseline during LIPUS stimulation.No obvious change in the fluorescence intensity tendency was observed after LIPUS stimulation in shRNA-Piezo1 cells,which was similar to the results in the GsMTx4-treated group.The phosphorylation ratio of ERK1/2 in MC3T3-E1 cells was significantly increased(P<0.01)after LIPUS stimulation.In addition,Phalloidin-iFluor-labeled F-actin filaments immediately accumulated in the perinuclear region after LIPUS stimulation,continued for 5 min,and then returned to their initial levels at 30 min.These results suggest that Piezo1 can transduce LIPUS-induced mechanical signals into intracellular calcium.The influx of Ca2+serves as a second messenger to activate ERK1/2 phosphorylation and perinuclear F-actin filament polymerization,which regulate the proliferation of MC3T3-E1 cells. 展开更多
关键词 STIMULATION Piezo1 ACTIVATION
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Bionic Mosaic Method of Panoramic Image Based on Compound Eye of Fly 被引量:8
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作者 Haipeng Chen Xuanjing Shen +1 位作者 xiaofei li Yushan Jin 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第4期440-448,共9页
To satisfy the requirements of real-time and high quality mosaics, a bionic compound eye visual system was designed by simulating the visual mechanism of a fly compound eye. Several CCD cameras were used in this syste... To satisfy the requirements of real-time and high quality mosaics, a bionic compound eye visual system was designed by simulating the visual mechanism of a fly compound eye. Several CCD cameras were used in this system to imitate the small eyes of a compound eye. Based on the optical analysis of this system, a direct panoramic image mosaic algorithm was proposed. Several sub-images were collected by the bionic compound eye visual system, and then the system obtained the overlapping proportions of these sub-images and cut the overlap sections of the neighboring images. Thus, a panoramic image with a large field of view was directly mosaicked, which expanded the field and guaranteed the high resolution. The experimental results show that the time consumed by the direct mosaic algorithm is only 2.2% of that by the traditional image mosaic algorithm while guaranteeing mosaic quality. Furthermore, the proposed method effectively solved the problem of misalignment of the mosaic image and eliminated mosaic cracks as a result of the illumination factor and other factors. This method has better real-time properties compared to other methods. 展开更多
关键词 bionic compound eye panoramic image image mosaic direct mosaic algorithm
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The Role of Initial Cloud Condensation Nuclei Concentration in Hail Using the WRF NSSL 2-moment Microphysics Scheme 被引量:5
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作者 xiaofei li Qinghong ZHANG Huiwen XUE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第9期1106-1120,共15页
The effects of the initial cloud condensation nuclei (CCN) concentrations (100-3000 mg-1) on hail properties were investigated in an idealized non-severe hail storm experiment using the Weather Research and Foreca... The effects of the initial cloud condensation nuclei (CCN) concentrations (100-3000 mg-1) on hail properties were investigated in an idealized non-severe hail storm experiment using the Weather Research and Forecasting (WRF) model, with the National Severe Storms Laboratory 2-moment microphysics scheme. The initial CCN concentration (CCNC) had obvious non-monotonic effects on the mixing ratio, number concentrations, and radius of hail, both in clouds and at the surface, with a CCNC threshold between 300 and 500 mg-1. An increasing CCNC is conducive (suppressive) to the amount of surface hail precipitation below (above) the CCNC threshold. The non-monotonic effects were due to both the thermodynamics and microphysics. Below the CCNC threshold, the mixing ratios with the increasing CCNC, resulting in more latent heat released of cloud droplets and ice crystals increased dramatically from condensation and frozen between 4 and 8 km and intensified updraft volume. The extent of the riming process, which is the primary process for hail production, increased dramatically. Above the CCNC threshold, the mixing ratio of cloud droplets and ice crystals increased continuously, but the maximum updraft volume was weakened because of reduced frozen latent heating at low level. The smaller ice crystals reduced the formation of hail and smaller clouds, with decreased rain water reducing riming efficiency so that graupel and hail also decreased with increasing CCNC, which is unfavorable for hail growth. 展开更多
关键词 CCN HAIL MICROPHYSICS THERMODYNAMICS threshold
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A novel superconducting magnetic levitation method to support the laser fusion capsule by using permanent magnets 被引量:5
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作者 Xiaojia li Tingting Xiao +3 位作者 Fengwei Chen Yingjuan Zhang xiaofei li Weidong Wu 《Matter and Radiation at Extremes》 SCIE EI CAS 2018年第3期104-109,共6页
A novel magnetic levitation support method is proposed, which can relieve the perturbation caused by traditional support methods andprovide more accurate position control of the capsule. This method can keep the perfe... A novel magnetic levitation support method is proposed, which can relieve the perturbation caused by traditional support methods andprovide more accurate position control of the capsule. This method can keep the perfect symmetry of the octahedral spherical hohlraum and hasthe characteristics in stability, tunability and simplicity. It is also favorable that all the results, such as supporting forces acting on the super-conducting capsule, are calculated analytically, and numerical simulations are performed to verify these results. A typical realistic design isproposed and discussed in detail. The superconducting coating material is suggested, and the required superconducting properties are listed.Damped oscillation of the floating capsule in thin helium gas is discussed, and the restoring time is estimated. 展开更多
关键词 ICF capsule support Magnetic levitation SYMMETRY
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Structural and functional characteristics of microbiota in oropharynx of sub-healthy children with gastrointestinal heat retention syndrome differentiated by traditional Chinese medicine 被引量:1
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作者 Jianhua Zhen He Yu +7 位作者 xiaofei li Fei Dong Zi'an Zheng Xueyan Ma Yuxiang Wan Tiegang liu Lu Fan Xiaohong Gu 《Journal of Traditional Chinese Medical Sciences》 CAS 2022年第3期230-236,共7页
Objective:To explore the structural and functional characteristics of microbiota in oropharynx of subhealthy children with gastrointestinal heat retention syndrome(GHRS)differentiated by traditional Chinese medicine,a... Objective:To explore the structural and functional characteristics of microbiota in oropharynx of subhealthy children with gastrointestinal heat retention syndrome(GHRS)differentiated by traditional Chinese medicine,and screen the biometric operational taxonomic units(OTUs)to assist the clinical diagnosis.Methods:We recruited children according to the“GHRS diagnostic scale”,collected their oropharyngeal swabs,and sequenced the 16 SrDNA V4 region.We described the bacterial structure with alpha-indexes,beta-distances,and relative abundances;moreover,we screened the differential genera/OTUs with Wilcoxon rank-sum test,Metagenome Seq analysis,and linear discriminant analysis effect size(LEf Se)analysis,in which biometric OTUs were selected to construct the receiver operating characteristic curve to verify the diagnostic value.The bacterial function was predicted with Kyoto Encyclopedia of Genes and Genomes pathways according to 16S rDNA gene by using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States.Results:The study population was composed of 10 children with GHRS and 10 healthy control children.GHRS children were more likely to overeat(gluttony,P=.033).Alpha-indexes,such as Sobs,abundancebased coverage estimator,Bootstrap,and Qstat,were significantly higher in the GHRS group,while betadistances did not exhibit any significant intergroup differences.There were 9 differently distributed nonpredominant genera between the groups in Wilcoxon rank-sum test,as well as 13 non-predominant genera in Metagenome Seq analysis and 3 non-predominant OTUs in LEfSe analysis.OTU44 and OTU196 were used to construct the receiver operating characteristic curve,and the area under curve was 0.92.Predicted functions showed that pathways related to oxidative phosphorylation and carbon metabolism were enriched in healthy control samples,while the pathway related to renin secretion was remarkably enriched in GHRS samples.Conclusion:Unique oropharyngeal microbial structure and function were identified in GHRS children.OTU44 and OTU196 were specific OTUs,which could be used as biomarkers of GHRS to assist clinical diagnosis. 展开更多
关键词 SUB-HEALTH Gastrointestinal heat retention syndrome Traditional Chinese medicine Microbiota in oropharynx 16S rDNA sequencing Children Differential genus Biometric operational taxonomic units
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