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Gene expression,transcription factor binding and histone modification predict leaf adaxial-abaxial polarity related genes
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作者 Wei Sun Zhicheng Zhang +2 位作者 Guusje Bonnema Xiaowu Wang Aalt Dirk Jan van Dijk 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第4期971-982,共12页
Leaf adaxial-abaxial(ad-abaxial)polarity is crucial for leaf morphology and function,but the genetic machinery governing this process remains unclear.To uncover critical genes involved in leaf ad-abaxial patterning,we... Leaf adaxial-abaxial(ad-abaxial)polarity is crucial for leaf morphology and function,but the genetic machinery governing this process remains unclear.To uncover critical genes involved in leaf ad-abaxial patterning,we applied a combination of in silico prediction using machine learning(ML)and experimental analysis.A Random Forest model was trained using genes known to influence ad-abaxial polarity as ground truth.Gene expression data from various tissues and conditions as well as promoter regulation data derived from transcription factor chromatin immunoprecipitation sequencing(ChIP-seq)was used as input,enabling the prediction of novel ad-abaxial polarity-related genes and additional transcription factors.Parallel to this,available and newly-obtained transcriptome data enabled us to identify genes differentially expressed across leaf ad-abaxial sides.Based on these analyses,we obtained a set of 111 novel genes which are involved in leaf ad-abaxial specialization.To explore implications for vegetable crop breeding,we examined the conservation of expression patterns between Arabidopsis and Brassica rapa using single-cell transcriptomics.The results demonstrated the utility of our computational approach for predicting candidate genes in crop species.Our findings expand the understanding of the genetic networks governing leaf ad-abaxial differentiation in agriculturally important vegetables,enhancing comprehension of natural variation impacting leaf morphology and development,with demonstrable breeding applications. 展开更多
关键词 Machine learning Leaf polarity Arabidopsis thaliana Brassica rapa Transcription factor
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Integrated interpretation of dual frequency induced polarization measurement based on wavelet analysis and metal factor methods 被引量:2
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作者 韩世礼 张术根 +2 位作者 柳建新 胡厚继 张文山 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第5期1465-1471,共7页
In mineral exploration, the apparent resistivity and apparent frequency (or apparent polarizability) parameters of induced polarization method are commonly utilized to describe the induced polarization anomaly. When... In mineral exploration, the apparent resistivity and apparent frequency (or apparent polarizability) parameters of induced polarization method are commonly utilized to describe the induced polarization anomaly. When the target geology structure is significantly complicated, these parameters would fail to reflect the nature of the anomaly source, and wrong conclusions may be obtained. A wavelet approach and a metal factor method were used to comprehensively interpret the induced polarization anomaly of complex geologic bodies in the Adi Bladia mine. Db5 wavelet basis was used to conduct two-scale decomposition and reconstruction, which effectively suppress the noise interference of greenschist facies regional metamorphism and magma intrusion, making energy concentrated and boundary problem unobservable. On the basis of that, the ore-induced anomaly was effectively extracted by the metal factor method. 展开更多
关键词 dual frequency induced polarization method wavelet analysis metal factor Arabian-Nubian shield volcanogenic massive sulfide deposit
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Role of immune relevant factors in regenerative processes of bone tissue: a bibliometric and visualized analysis
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作者 Jie Wang Li-Qing Jiang Hao-Peng Li 《Biomedical Engineering Communications》 2024年第4期8-19,共12页
Background:There is a deficiency of bibliometric and visually represented analysis in research on the immunological related variables involved in bone tissue regeneration.Using bibliometric and visual analysis,this st... Background:There is a deficiency of bibliometric and visually represented analysis in research on the immunological related variables involved in bone tissue regeneration.Using bibliometric and visual analysis,this study sought to thoroughly examine the hotspots and future directions in the investigation of immunological important variables in bone tissue regeneration.Methods:The Web of Science Core Collection(WoSCC)database was searched and a collection of published works on the subject of immunological related factors in bone tissue regeneration between 2000 and 2021 was generated.The data chosen from the WoSCC were then subjected to a systematic bibliometric and visualized analysis using the online bibliometric analytics system,Apache ECharts,VOSviewer,Bibliographic Items Co-occurrence Matrix Builder 2.0,and Gcluto 1.0.Results:For this investigation,1,088 publications on the involvement of immune related components in bone tissue regeneration were chosen.Between 2000 and 2021,China maintained its supremacy in global research on the function of immune related components in bone tissue regeneration.Shanghai Jiao Tong University is the most productive institution.Biomaterials has published the most publications on the involvement of immune-related components in bone tissue regeneration.Xiao Y,Schmidt-Bleek K,and Ignatius A all played important roles in the study of immune-related variables in bone tissue regeneration.Research on the role of immune relevant factors in bone tissue regeneration has identified five hotspots:(1)macrophage-based immunomodulation on osteogenesis of mesenchymal stem cells(MSCs);(2)biomaterials for bone repair in bone tissue engineering;(3)osteoimmunomodulation mediated by inflammation and macrophages during bone healing;(4)osteoimmunomodulation in angiogenesis during bone regeneration;and(5)the effect of macrophage polarization regulated by bone tissue engineering on osteogenic differentiation of MSCs as bone tissue.Conclusion:This study represents the first-ever bibliometric and visualized examination of how immune factors contribute to bone tissue regeneration.The focus and forthcoming direction in bone regeneration research will be on macrophage-driven immunomodulation in the process of bone regeneration. 展开更多
关键词 immune relevant factors MACROPHAGES macrophage-based immunomodulation macrophage polarization regenerative processes bone tissue
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Determination of Structure and Polarity of Si C Single Crystal by X-Ray Diffraction Technique 被引量:1
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作者 郑新和 渠波 +2 位作者 王玉田 杨辉 梁骏吾 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第1期35-39,共5页
Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam pl... Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam ple has a6 H modification.The difference between the integrated intensities m easured byω scan in the triple- axis diffraction set- up finds some convincing evidence that the surface is either a Si- terminated face or C- terminated face.The experi- mental ratios of| F( 0 0 0 L) | 2 / | F( 0 0 0 L) | 2 are in good agreem entwith the calculated ones after the dispersion cor- rections to the atomic scattering factors( L=6 ,12 and18,respectively) .Thus,this m easurem ent technique is con- venient for the application of the materials with remarkable surface polarity. 展开更多
关键词 Si C single crystal polarity hexagonal6 H scattering factor
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BLIND PARAFAC SIGNAL DETECTION FOR UNIFORM CIRCULAR ARRAY WITH POLARIZATION SENSITIVE ANTENNAS 被引量:1
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作者 张小飞 黄希珠 徐大专 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第4期291-296,共6页
The received signal of the polarization sensitive array is proved to have trilinear model characteristics. The blind parallel factor(PARAFAC) signal detection algorithm for the polarization sensitive array is propos... The received signal of the polarization sensitive array is proved to have trilinear model characteristics. The blind parallel factor(PARAFAC) signal detection algorithm for the polarization sensitive array is proposed. The trilinear alternating least square (TALS) algorithm is used to abtain the source matrix, and then the matrix is judged. Simulation results show that the bit error rate (BER) of the detection algorithm is close to that of the non-blind decorrelating method and the algorithm works well under the array error condition. BER difference between the non-blind method and this algorithm is less than 2 dB under a high SNR. The algorithm is blind and robust. The channel fading, the direction of arrive(DOA) imformation and the polarization information are needless in the algorithm. 展开更多
关键词 polarization sensitive array parallel factor trilinear model complete polarization uniform circular array
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M2型巨噬细胞衍生外泌体促进小胶质细胞M2型极化
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作者 方俊 魏伟 +5 位作者 薛亚婷 崔臣龙 卫嘉晟 石筱 杨丽娟 杨保仲 《中国组织工程研究》 CAS 北大核心 2025年第25期5320-5327,共8页
背景:目前对于M2型巨噬细胞衍生外泌体的研究多集中于促进伤口愈合及成骨细胞的增殖和分化,而很少有研究关注其对小胶质细胞表型的调控作用。目的:探讨M2型巨噬细胞衍生外泌体对于小胶质细胞的表型调控作用及分子机制。方法:①提取骨髓... 背景:目前对于M2型巨噬细胞衍生外泌体的研究多集中于促进伤口愈合及成骨细胞的增殖和分化,而很少有研究关注其对小胶质细胞表型的调控作用。目的:探讨M2型巨噬细胞衍生外泌体对于小胶质细胞的表型调控作用及分子机制。方法:①提取骨髓原代巨噬细胞,用50 ng/m L白细胞介素4刺激巨噬细胞24 h促进巨噬细胞M2型极化,流式细胞术和细胞免疫荧光鉴定M2型巨噬细胞标志物CD206;②提取和鉴定M2型巨噬细胞衍生外泌体;③将小胶质细胞BV2随机分为3组:对照组、脂多糖组、治疗组,对照组不做处理,脂多糖组加入500 ng/m L脂多糖干预24 h,治疗组同时加入500 ng/m L脂多糖和25μg/m L M2型巨噬细胞衍生外泌体干预24 h,ELISA检测培养上清中肿瘤坏死因子α和白细胞介素10的分泌量,q RT-PCR检测细胞中诱导型一氧化氮合酶、精氨酸酶1、白细胞介素1β和白细胞介素10的m RNA表达,Western blot检测诱导型一氧化氮合酶、精氨酸酶1的蛋白表达以及核因子κB信号通路相关蛋白表达。结果与结论:①ELISA结果显示,与对照组相比,脂多糖组肿瘤坏死因子α分泌明显增多;与脂多糖组相比,治疗组肿瘤坏死因子α的分泌减少而白细胞介素10的分泌增多;②q RT-PCR结果显示,与对照组相比,脂多糖组白细胞介素1β、诱导型一氧化氮合酶m RNA表达升高;与脂多糖组相比,治疗组白细胞介素1β、诱导型一氧化氮合酶m RNA表达降低,白细胞介素10、精氨酸酶1 m RNA表达升高;③Western blot结果显示,与对照组相比,脂多糖组诱导型一氧化氮合酶蛋白表达升高;与脂多糖组相比,治疗组诱导型一氧化氮合酶蛋白表达降低,而精氨酸酶1蛋白表达升高;(4)与对照组相比,脂多糖组核因子κB信号通路中P65、p-IκB-α蛋白表达降低;与脂多糖组相比,治疗组P65、p-IκB-α蛋白表达升高。结果表明:M2型巨噬细胞衍生外泌体可以显著抑制脂多糖诱导小胶质细胞的炎症反应,促进抗炎因子白细胞介素10的表达,抑制促炎因子肿瘤坏死因子α、白细胞介素1β的表达,促进小胶质细胞表型由M1型向M2型极化,其机制可能与M2型巨噬细胞衍生外泌体抑制核因子κB信号通路激活有关。 展开更多
关键词 M2巨噬细胞 外泌体 小胶质细胞 炎症 NF-ΚB信号通路 神经病理性疼痛 极化
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莱斯信道中Polar码的构造及性能分析 被引量:1
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作者 范海玲 赵生妹 郑宝玉 《信号处理》 CSCD 北大核心 2015年第9期1062-1066,共5页
Polar码是由Arikan提出的一种新的编码方式。它是基于信道极化理论,被证明在二进制离散无记忆信道下能够获得信道对称容量。本文给出了Polar码在莱斯信道下的构造及性能分析,针对莱斯信道已知信道边信息(CSI)和未知信道边信息(NCSI)两... Polar码是由Arikan提出的一种新的编码方式。它是基于信道极化理论,被证明在二进制离散无记忆信道下能够获得信道对称容量。本文给出了Polar码在莱斯信道下的构造及性能分析,针对莱斯信道已知信道边信息(CSI)和未知信道边信息(NCSI)两种情况分别进行Polar码的构造。仿真结果表明:相比于LDPC码,Polar码的性能更加优良。此外,莱斯因子K越大,Polar码的误比特率就越小。Polar码在信道边信息已知的情况下性能比信道边信息未知时的好。因此Polar码在莱斯衰落信道中具有很好的性能,非常适合未来移动通信技术。 展开更多
关键词 polar码的构造 莱斯信道 误比特率 莱斯因子
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IRF5 regulates lung macrophages M2 polarization during severe acute pancreatitis in vitro 被引量:14
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作者 Kang Sun Song-Bing He +5 位作者 Jian-Guo Qu Sheng-Chun Dang Ji-Xiang Chen Ai-Hua Gong Rong Xie Jian-Xin Zhang 《World Journal of Gastroenterology》 SCIE CAS 2016年第42期9368-9377,共10页
AIM To investigate the role of interferon regulatory factor 5(IRF5) in reversing polarization of lung macrophages during severe acute pancreatitis(SAP) in vitro.METHODS A mouse SAP model was established by intraperito... AIM To investigate the role of interferon regulatory factor 5(IRF5) in reversing polarization of lung macrophages during severe acute pancreatitis(SAP) in vitro.METHODS A mouse SAP model was established by intraperitoneal(ip) injections of 20 μg/kg body weight caerulein. Pathological changes in the lung were observed by hematoxylin and eosin staining. Lung macrophages were isolated from bronchoalveolar lavage fluid. The quantity and purity of lung macrophages were detectedby fluorescence-activated cell sorting and evaluated by real-time polymerase chain reaction(RT-PCR). They were treated with IL-4/IRF5 specific siR NA(IRF5 siR NA) to reverse their polarization and were evaluated by detecting markers expression of M1/M2 using RTPCR.RESULTS SAP associated acute lung injury(ALI) was induced successfully by ip injections of caerulein, which was confirmed by histopathology. Lung macrophages expressed high levels of IRF5 as M1 phenotype during the early acute pancreatitis stages. Reduction of IRF5 expression by IRF5 siR NA reversed the action of macrophages from M1 to M2 phenotype in vitro. The expressions of M1 markers, including IRF5(S + IRF5 siR NA vs S + PBS, 0.013 ± 0.01 vs 0.054 ± 0.047, P < 0.01), TNF-α(S + IRF5 siR NA vs S + PBS, 0.0003 ± 0.0002 vs 0.019 ± 0.018, P < 0.001), iN OS(S + IRF5 siR NA vs S + PBS, 0.0003 ± 0.0002 vs 0.026 ± 0.018, P < 0.001) and IL-12(S + IRF5 si RNA vs S + PBS, 0.000005 ± 0.00004 vs 0.024 ± 0.016, P < 0.001), were decreased. In contrast, the expressions of M2 markers, including IL-10(S + IRF5 siR NA vs S + PBS, 0.060 ± 0.055 vs 0.0230 ± 0.018, P < 0.01) and Arg-1(S + IRF5 siR NA vs S + PBS, 0.910 ± 0.788 vs 0.0036 ± 0.0025, P < 0.001), were increased. IRF5 si RNA could reverse the lung macrophage polarization more effectively than IL-4.CONCLUSION Treatment with IRF5 siR NA can reverse the pancreatitisinduced activation of lung macrophages from M1 phenotype to M2 phenotype in SAP associated with ALI. 展开更多
关键词 Interferon regulatory factor 5 Macrophage polarization Severe acute pancreatitis SiR NA
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Bone marrow mesenchymal stem cells induce M2 microglia polarization through PDGF-AA/MANF signaling 被引量:7
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作者 Fan Yang Wen-Bin Li +4 位作者 Ye-Wei Qu Jin-Xing Gao Yu-Shi Tang Dong-Jie Wang Yu-Jun Pan 《World Journal of Stem Cells》 SCIE CAS 2020年第7期633-657,共25页
BACKGROUND Bone marrow mesenchymal stem cells(BMSCs)are capable of shifting the microglia/macrophages phenotype from M1 to M2,contributing to BMSCsinduced brain repair.However,the regulatory mechanism of BMSCs on micr... BACKGROUND Bone marrow mesenchymal stem cells(BMSCs)are capable of shifting the microglia/macrophages phenotype from M1 to M2,contributing to BMSCsinduced brain repair.However,the regulatory mechanism of BMSCs on microglia/macrophages after ischemic stroke is unclear.Recent evidence suggests that mesencephalic astrocyte-derived neurotrophic factor(MANF)and plateletderived growth factor-AA(PDGF-AA)/MANF signaling regulate M1/M2 macrophage polarization.AIM To investigate whether and how MANF or PDGF-AA/MANF signaling influences BMSCs-mediated M2 polarization.METHODS We identified the secretion of MANF by BMSCs and developed transgenic BMSCs using a targeting small interfering RNA for knockdown of MANF expression.Using a rat middle cerebral artery occlusion(MCAO)model transplanted by BMSCs and BMSCs-microglia Transwell coculture system,the effect of BMSCsinduced downregulation of MANF expression on the phenotype of microglia/macrophages was tested by Western blot,quantitative reverse transcription-polymerase chain reaction,and immunofluorescence.Additionally,microglia were transfected with mimics of miR-30a*,which inuenced expression of X-box binding protein(XBP)1,a key transcription factor that synergized with activating transcription factor 6(ATF6)to govern MANF expression.We examined the levels of miR-30a*,ATF6,XBP1,and MANF after PDGF-AA treatment in the activated microglia.RESULTS Inhibition of MANF attenuated BMSCs-induced functional recovery and decreased M2 marker production,but increased M1 marker expression in vivo or in vitro.Furthermore,PDGF-AA treatment decreased miR-30a*expression,had no influence on the levels of ATF6,but enhanced expression of both XBP1 and MANF.CONCLUSION BMSCs-mediated MANF paracrine signaling,in particular the PDGF-AA/miR-30a*/XBP1/MANF pathway,synergistically mediates BMSCs-induced M2 polarization. 展开更多
关键词 Mesencephalic astrocyte-derived neurotrophic factor Bone marrow mesenchymal stem cell Microglia/macrophage polarization Endoplasmic reticulum stress Cerebral ischemia/reperfusion injury
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Fast PARAFAC decomposition with application to polarization sensitive array parameter estimations 被引量:1
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作者 LI Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期714-722,共9页
In tensor theory, the parallel factorization (PARAFAC)decomposition expresses a tensor as the sum of a set of rank-1tensors. By carrying out this numerical decomposition, mixedsources can be separated or unknown sys... In tensor theory, the parallel factorization (PARAFAC)decomposition expresses a tensor as the sum of a set of rank-1tensors. By carrying out this numerical decomposition, mixedsources can be separated or unknown system parameters can beidentified, which is the so-called blind source separation or blindidentification. In this paper we propose a numerical PARAFACdecomposition algorithm. Compared to traditional algorithms, wespeed up the decomposition in several aspects, i.e., search di-rection by extrapolation, suboptimal step size by Gauss-Newtonapproximation, and linear search by n steps. The algorithm is ap-plied to polarization sensitive array parameter estimation to showits usefulness. Simulations verify the correctness and performanceof the proposed numerical techniques. 展开更多
关键词 tensor decomposition parallel factorization(PARAFAC) alternating least squares (ALS) polarization sensi-tive array (PSA)
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Complex variable approach in studying modified polarization saturation model in two-dimensional semipermeable piezoelectric media 被引量:1
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作者 S. SINGH K. SHARMA R. R. BHARGAVA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第11期1517-1532,共16页
A modified polarization saturation model is proposed and addressed math- ematically using a complex variable approach in two-dimensional (2D) semipermeable piezoelectric media. In this model, an existing polarizatio... A modified polarization saturation model is proposed and addressed math- ematically using a complex variable approach in two-dimensional (2D) semipermeable piezoelectric media. In this model, an existing polarization saturation (PS) model in 2D piezoelectric media is modified by considering a linearly varying saturated normal electric displacement load in place of a constant normal electric displacement load, applied on a saturated electric zone. A centre cracked infinite 2D piezoelectric domain subject to an arbitrary poling direction and in-plane electromechanical loadings is considered for the analytical and numerical studies. Here, the problem is mathematically modeled as a non-homogeneous Riemann-Hilbert problem in terms of unknown complex potential functions representing electric displacement and stress components. Having solved the Hilbert problem, the solutions to the saturated zone length, the crack opening displace- ment (COD), the crack opening potential (COP), and the local stress intensity factors (SIFs) are obtained in explicit forms. A numerical study is also presented for the proposed modified model, showing the effects of the saturation condition on the applied electrical loading, the saturation zone length, and the COP. The results of fracture parameters obtained from the proposed model are compared with the existing PS model subject to electrical loading, crack face conditions, and polarization angles. 展开更多
关键词 complex variable fracture parameter local stress intensity factor (SIF) piezoelectric polarization saturation (PS) model
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Light polarization and color from guided‐mode resonance filter
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作者 Zhibin Ren Yahui Sun +2 位作者 Jiasheng Hu Mengsi Li Kaipeng Zhang 《光电工程》 CAS CSCD 北大核心 2017年第11期1052-1055,共4页
The characteristics of reflected light of a 1-D guided-mode resonance filter(GMRF)are studied in this paper.A triple-layer GMRF is designed by using the finite difference time domain method under non-polarized light i... The characteristics of reflected light of a 1-D guided-mode resonance filter(GMRF)are studied in this paper.A triple-layer GMRF is designed by using the finite difference time domain method under non-polarized light illumination.Numerical results show that the reflectance spectra of TE and TM polarizations can be changed by altering the fill factor f of the GMRF.Moreover,by calculating the color of the reflected light with the chromaticity theory,we find that the color of reflected light becomes pure when f is 0.9.The results show that the color and polarization degree of the reflected light of a GMRF are tunable by altering the fill factor. 展开更多
关键词 《光电工程》 英文摘要 期刊 编辑工作
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信息茧房效应下用户群体极化形成机理研究 被引量:1
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作者 张瀚予 丁怡宁 郭思琪 《图书与情报》 CSSCI 北大核心 2024年第3期132-144,共13页
智能媒体时代下,进一步探究信息茧房效应对用户群体极化行为意愿的影响,能为构建良好的社交媒体平台生态提供建议。文章基于“刺激-机体-反应”框架与信息生态理论,从信息茧房的同质化特征内涵出发,分析信息茧房形成机理并构建信息茧房... 智能媒体时代下,进一步探究信息茧房效应对用户群体极化行为意愿的影响,能为构建良好的社交媒体平台生态提供建议。文章基于“刺激-机体-反应”框架与信息生态理论,从信息茧房的同质化特征内涵出发,分析信息茧房形成机理并构建信息茧房效应下用户群体极化作用机理模型,利用问卷调查收集样本,通过结构方程模型展开实证研究。研究结果显示,信息同质化、选择性接触、群际情绪和社会比较频率在用户群体极化行为意愿形成过程中发挥重要作用。同时,用户态度极化也是信息茧房效应下用户群体极化行为意愿的影响因素。 展开更多
关键词 信息茧房 群体极化 行为意愿 影响因素
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锂电池自适应无迹H∞滤波SOC估计研究 被引量:1
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作者 钱伟 赵大中 +2 位作者 郭向伟 王亚丰 李文静 《储能科学与技术》 CAS CSCD 北大核心 2024年第11期4078-4088,共11页
荷电状态(state of charge,SOC)作为表征锂电池剩余电量的关键指标,其精确估计对于合理使用电池电量、保障电池安全具有重要意义。本文针对基于H∞滤波(H infinity filter,HIF)估计SOC时鲁棒性好但估计精度低的问题,提出一种自适应无迹... 荷电状态(state of charge,SOC)作为表征锂电池剩余电量的关键指标,其精确估计对于合理使用电池电量、保障电池安全具有重要意义。本文针对基于H∞滤波(H infinity filter,HIF)估计SOC时鲁棒性好但估计精度低的问题,提出一种自适应无迹H∞滤波(adaptive unscented H infinity filter,AU_HIF)SOC估计方法,以提高SOC估计精度。首先,选择能够在精度和复杂度间取得良好平衡的双极化(dual polarization,DP)等效电路模型进行新型估计算法的设计;其次,结合无迹卡尔曼滤波(unscented Kalman filter,UKF)算法相比于传统扩展卡尔曼滤波(extended Kalman filter,EKF)算法更适用于非线性系统状态估计的特点,文章基于先验误差协方差矩阵设计新型渐消因子,实现自适应无迹H∞滤波算法的设计,以减小陈旧测量值对估计结果的影响,提高滤波算法的跟踪能力及估计精度。最后,通过搭建自主实验平台获取实际模拟工况数据,验证了文章所提自适应无迹H∞滤波算法相比于传统H∞滤波算法、传统UKF算法和其他类型改进H∞滤波算法具有更高的估计精度及更好的鲁棒性。文章研究内容对提高新能源汽车、储能电站等电池系统的SOC估计精度具有重要意义。 展开更多
关键词 锂电池 SOC H∞滤波 DP模型 渐消因子
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Diversity–Multiplexing Tradeoff and Outage Performance for 2&times;2 Dual-Polarized Uncorrelated Rice MIMO Channels
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作者 Yanping Huang Guangliang Ren 《Communications and Network》 2013年第3期319-326,共8页
In this paper, diversity-multiplexing tradeoff (DMT) curve for 2×2 Dual-Polarized uncorrelated Rice MIMO channels is studied. Exact expressions for statistic information of mutual information exponent are derived... In this paper, diversity-multiplexing tradeoff (DMT) curve for 2×2 Dual-Polarized uncorrelated Rice MIMO channels is studied. Exact expressions for statistic information of mutual information exponent are derived. Impacts of channel parameters such as signal to noise ratio (SNR), k-factor and cross polarization discrimination (XPD) on mutual information exponent are analyzed. Compared to conventional single-polarized (SP) Rice MIMO systems, a qualitatively different behavior is observed for DP Rice systems. The work in this paper, allows identifying quantitatively for which channels (k-factor) and SNR levels the use of dual polarization becomes beneficial. Gamma or lognormal distribution are used to describe mutual information component, and a theoretical formulation for finite-SNR DMT curve in 2×2 DP uncorrelated Rice channels is presented for the first time, which is valid in low and medium SNRs when multiplexing gain is larger than 0.75. 展开更多
关键词 DMT curve Dual-polarized Uncorrelated RICE Channel Mutual Information EXPONENT K-factor Outage Probablity Approximation
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高铁开通与边缘城市金融要素发展:极化还是涓滴效应
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作者 林承铎 刘青山 +1 位作者 施昱年 郎昱 《工程管理科技前沿》 CSSCI 北大核心 2024年第3期55-61,共7页
高铁开通对金融要素在核心城市和边缘城市流动的影响一直存在争议。本文采用区位熵、城市的金融规模和人口流动等因素区分金融要素集中的核心城市和相对不集中的边缘城市,并使用双重差分(DID)法进行实证检验。结果显示,高铁开通使边缘... 高铁开通对金融要素在核心城市和边缘城市流动的影响一直存在争议。本文采用区位熵、城市的金融规模和人口流动等因素区分金融要素集中的核心城市和相对不集中的边缘城市,并使用双重差分(DID)法进行实证检验。结果显示,高铁开通使边缘城市与核心城市的金融要素发展差距扩大,极化效应凸显,这一现象在不同区域间存在异质性,且距离愈远极化效应表现愈显著。伴随极化效应,区域内金融要素高度集中,金融要素市场潜力下降。研究结论为高铁开通下边缘城市扮演的金融要素角色提供了经验证据。 展开更多
关键词 高铁 金融要素 边缘城市 极化效应 涓滴效应
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MS19通过抑制IRF5表达调控巨噬细胞极化减轻CTD-ILD肺部炎症的作用研究
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作者 陈珊珊 明倩文 +1 位作者 肖恩华 王晓红 《中南药学》 CAS 2024年第5期1178-1185,共8页
目的 探讨MS19通过靶向干扰素调节因子5(IRF5)对结缔组织疾病相关肺间质病变(CTD-ILD)小鼠模型肺部炎症的治疗作用及其相关机制。方法 动物实验:构建CTD-ILD小鼠模型,予以MS19干预,研究MS19对CTD-ILD小鼠肺部炎症的影响。细胞实验:对RAW... 目的 探讨MS19通过靶向干扰素调节因子5(IRF5)对结缔组织疾病相关肺间质病变(CTD-ILD)小鼠模型肺部炎症的治疗作用及其相关机制。方法 动物实验:构建CTD-ILD小鼠模型,予以MS19干预,研究MS19对CTD-ILD小鼠肺部炎症的影响。细胞实验:对RAW264.7细胞进行OE-IRF5转染,然后予以MS19干预,研究MS19对IRF5调控的巨噬细胞M1型极化及炎症反应的影响。结果 动物实验:CTD-ILD小鼠出现明显的肺部炎症,小鼠支气管肺泡灌洗液(BALF)中IRF5的表达增高、巨噬细胞M1型极化增加及促炎因子(TNF-α、IL-6和IL-1β)的表达升高;而MS19干预后,CTD-ILD小鼠的肺部炎症减轻,BALF中IRF5表达降低、巨噬细胞M1型极化减少及促炎因子表达下降。细胞实验:脂多糖诱导巨噬细胞M1型极化、促炎因子表达增加;转染OE-IRF5后,巨噬细胞M1型极化增加、促炎因子表达增加;MS19干预后,巨噬细胞M1型极化减少、促炎因子表达减少。结论 MS19通过靶向抑制IRF5调控巨噬细胞极化及炎症反应,从而改善CTD-ILD的肺部炎症,为防治CTD-ILD提供潜在靶点和候选药物。 展开更多
关键词 MS19 寡聚脱氧核糖核苷酸 干扰素调节因子5 巨噬细胞极化 结缔组织疾病相关肺间质病变
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径向偏振高阶贝塞尔-高斯涡旋光束在海洋湍流中的传输特性
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作者 孙顺红 刘永欣 《宁夏大学学报(自然科学版)》 CAS 2024年第2期138-143,共6页
采用分步相位屏的方法,研究了径向偏振高阶贝塞尔-高斯涡旋光束在海洋湍流中的光强特性和闪烁特性.研究发现,径向偏振高阶贝塞尔-高斯涡旋光束传输一段距离后,其中心区域光强受自身特性的影响;对于不同强度的海洋湍流,随着均方温度耗散... 采用分步相位屏的方法,研究了径向偏振高阶贝塞尔-高斯涡旋光束在海洋湍流中的光强特性和闪烁特性.研究发现,径向偏振高阶贝塞尔-高斯涡旋光束传输一段距离后,其中心区域光强受自身特性的影响;对于不同强度的海洋湍流,随着均方温度耗散率的增大,光束所对应的轴上区域的闪烁因子也越大.相较于线偏振光束和径向偏振光束,径向偏振高阶贝塞尔-高斯涡旋光束在海洋湍流中的传输受湍流的影响较小.研究还发现,传输一段距离后,径向偏振高阶贝塞尔-高斯涡旋光束(n≥1)的拓扑荷数越高,光束所对应的闪烁因子越小.另外,相对于径向偏振高阶贝塞尔-高斯涡旋光束(n≥1),拓扑荷数n=0的径向偏振零阶贝塞尔-高斯涡旋光束具有较低的闪烁因子. 展开更多
关键词 闪烁因子 数值模拟 海洋湍流 传输特性 径向偏振
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吲哚丙酸抑制小胶质细胞M1极化治疗脊髓损伤 被引量:2
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作者 滕益霖 席德双 +4 位作者 冯彦斌 梁宇 邓豪 曾高峰 宗少晖 《中国组织工程研究》 CAS 北大核心 2024年第31期5010-5016,共7页
背景:吲哚丙酸被证明可减轻糖尿病所致的中枢神经系统炎症,但其能否抑制小胶质细胞M1极化治疗脊髓损伤,目前仍缺乏相关研究。目的:通过细胞实验及动物实验探究吲哚丙酸抑制小胶质细胞M1极化治疗脊髓损伤的机制。方法:①体外实验:CCK8法... 背景:吲哚丙酸被证明可减轻糖尿病所致的中枢神经系统炎症,但其能否抑制小胶质细胞M1极化治疗脊髓损伤,目前仍缺乏相关研究。目的:通过细胞实验及动物实验探究吲哚丙酸抑制小胶质细胞M1极化治疗脊髓损伤的机制。方法:①体外实验:CCK8法检测BV2细胞活性并筛选最佳的吲哚丙酸使用浓度;然后将BV2细胞分为对照组、单纯给药组(50μmol/L吲哚丙酸)、脂多糖组(100 ng/mL脂多糖)、治疗组(100 ng/mL脂多糖+50μmol/L吲哚丙酸),采用Griess法检测一氧化氮含量;实时荧光定量PCR、Western Blot检测促炎相关因子的mRNA和蛋白的表达;细胞免疫荧光染色检测诱导型一氧化氮合酶的表达;Seahorse实验检测BV2细胞糖酵解压力水平。②体内实验:将30只SD大鼠随机分成3组:假手术组、脊髓损伤组、吲哚丙酸组。采用BBB评分与斜板实验评估大鼠脊髓损伤后功能恢复情况;免疫荧光染色检测脊髓组织中小胶质细胞诱导型一氧化氮合酶的表达情况;ELISA检测脊髓组织中促炎因子白细胞介素1β及肿瘤坏死因子α蛋白表达水平。结果与结论:①体外实验:当吲哚丙酸浓度>50μmol/L时明显抑制BV2细胞活性;吲哚丙酸可通过抑制核因子κB信号通路的激活,进而抑制促炎因子(白细胞介素1β、肿瘤坏死因子α)及BV2细胞M1极化标志物诱导型一氧化氮合酶的mRNA及蛋白表达水平;吲哚丙酸能明显降低脂多糖诱导BV2细胞的糖酵解水平。②体内实验:脊髓损伤大鼠给予吲哚丙酸干预后,BBB评分与斜板实验角度明显增加;脊髓组织中M1极化小胶质细胞的数量显著下降及促炎因子(白细胞介素1β、肿瘤坏死因子α)蛋白表达水平明显降低。③结果说明,吲哚丙酸可通过抑制小胶质细胞M1极化改善炎症微环境促进脊髓损伤后功能恢复。 展开更多
关键词 吲哚丙酸 脊髓损伤 小胶质细胞 M1极化 促炎因子 信号通路
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雷公藤内酯醇对脑缺血再灌注大鼠小胶质细胞M1/M2型极化的影响 被引量:1
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作者 白雪 王亚博 +3 位作者 闫伟娇 霍好利 邢瑞敏 王雪莹 《世界中医药》 CAS 北大核心 2024年第1期19-25,共7页
目的:探讨雷公藤内酯醇(TPL)对脑缺血再灌注(CIR)大鼠小胶质细胞M1/M2型极化的影响。方法:选取192只SD大鼠设假手术组、模型组、丁苯酞(6 mg/kg)组和TPL低、中、高(0.2、0.4、0.8 mg/kg)剂量组,每组32只。除假手术组外,其余5组采用线栓... 目的:探讨雷公藤内酯醇(TPL)对脑缺血再灌注(CIR)大鼠小胶质细胞M1/M2型极化的影响。方法:选取192只SD大鼠设假手术组、模型组、丁苯酞(6 mg/kg)组和TPL低、中、高(0.2、0.4、0.8 mg/kg)剂量组,每组32只。除假手术组外,其余5组采用线栓阻断大脑中动脉2 h的方法复制CIR大鼠模型。各组均于造模前3 d开始给药,1次/d,再灌注24 h后,检测大鼠神经功能、脑梗死率、脑含水量,观察缺血侧皮层神经元病理学变化;酶联免疫吸附试验法(ELISA)检测缺血侧皮层组织炎症介质含量,免疫荧光标记法检测小胶质细胞表型M1型标志物CD86/离子钙结合衔接分子-1(Ionized Calcium-binding Adapter Molecule-1,Iba-1)、M2型标志物CD206/Iba-1,蛋白质免疫印迹法检测Toll样受体4(TLR4)、核因子κB、p-核因子κB蛋白表达。结果:与模型组比较,TPL中、高剂量组和丁苯酞组神经功能缺失评分、脑梗死率、脑含水量显著降低(P<0.05);缺血侧皮层神经元病理学变化明显改善,肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、细胞间黏附分子-1(ICAM-1)含量显著降低而IL-10含量显著升高,CD86/Iba-1阳性细胞率显著降低,CD206/Iba-1阳性细胞率显著升高(P<0.05);缺血侧皮层组织Toll样受体4(TLR4)、p-核因子κB表达显著下调,p-核因子κB/核因子κB比值显著降低(P<0.05)。除神经功能缺失评分、脑含水量、IL-1β含量外,TPL高剂量组对其他指标的影响均优于丁苯酞组(P<0.05)。结论:TPL可抑制大鼠CIR损伤,可能与促进小胶质细胞M1型向M2型极化,抑制TLR4/核因子κB通路活化及炎症反应有关。 展开更多
关键词 雷公藤内酯醇 脑缺血再灌注 小胶质细胞 极化 神经功能 TOLL样受体4 核因子ΚB 炎症
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