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Recombinant expression of a novel Mytilus defensin in Pichia pastoris 被引量:1
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作者 XIAO Wenhui SONG Fang +4 位作者 CHEN Chuanyue HUANG Fangfang YANG Qiaomei ZHANG Xiaolin LIAO Zhi 《生物工程学报》 北大核心 2026年第2期852-864,共13页
Mytilus contain abundant antimicrobial peptides(AMPs)that play a key role in the innate immunity.However,heterologous production of these AMPs remains challenging due to their short sequences,multiple disulfide bonds,... Mytilus contain abundant antimicrobial peptides(AMPs)that play a key role in the innate immunity.However,heterologous production of these AMPs remains challenging due to their short sequences,multiple disulfide bonds,and high content of cationic amino acids,which hinder functional expression in prokaryotic systems such as Escherichia coli.To establish a eukaryotic recombinant expression system for the AMPs of mussel and obtain recombinant mussel AMPs for subsequent studies,we reported the successful recombinant expression of myticofensin B1,a novel defensin-like AMP identified previously in Mytiluscoruscus,using the eukaryotic host Pichia pastoris.The codon-optimized gene encoding the mature myticofensin-B1(composed of 65 amino acid residues,including 6 conserved cysteine residues)was cloned into a pPICZαA vector and expressed in P.pastoris GS115.Structural fidelity of the recombinant peptide was confirmed by liquid chromatography-tandem mass spectrometry(LC-MS/MS),showing a molecular weight of 8849.9 Da,which was consistent with the theoretical prediction.Functional assays demonstrated a broad-spectrum antimicrobial activity of the recombinant myticofensin-B1,with stronger inhibition against Gram-negative bacteria.Scanning electron microscopy revealed different effects of the recombinant myticofensin-B1 against different bacteria.In addition,the recombinant myticofensin-B1 exhibited a very low hemolytic activity against sheep red blood cells and weak cytotoxicity against human A549 lung cancer cells.This study establishes P.pastoris as a powerful platform to produce functional mussel AMP and highlights the potential of the recombinant myticofensin-B1 as a therapeutic agent for aquaculture pathogens and infections. 展开更多
关键词 Mytilus coruscus myticofensin recombinant expression antimicrobial peptide Pichia pastoris
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基于PCIe的链式DMA控制器设计与实现
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作者 王洪良 郭振华 +3 位作者 牟奇 卢圣才 徐亚明 于泉泉 《计算机研究与发展》 北大核心 2026年第1期28-40,共13页
近年来,国产可编程门阵列(field programmable gate array,FPGA)厂商虽发展迅速,但在数据中心部署FPGA异构加速器时仍面临挑战。相较于赛灵思、英特尔等国际厂商,国产厂商普遍缺乏PCIe设备与主机间高速传输的解决方案,尤其在高性能直接... 近年来,国产可编程门阵列(field programmable gate array,FPGA)厂商虽发展迅速,但在数据中心部署FPGA异构加速器时仍面临挑战。相较于赛灵思、英特尔等国际厂商,国产厂商普遍缺乏PCIe设备与主机间高速传输的解决方案,尤其在高性能直接内存访问(direct memory access,DMA)控制器设计领域存在明显短板。为解决该问题,设计并实现了基于PCIe的多通道链式DMA控制器。采用独立描述符控制器管理各通道,共享数据搬移器,降低对FPGA逻辑资源的消耗。采用链式结构实现描述符管理,减少中断对CPU的压力,满足主机与设备连续高速传输的需求。创新性地构建内部信息异步与预处理的架构,实现数据流水化处理,显著提升带宽利用率以及传输性能。经测试,在PCIe Gen3x8下,主机与国产FPGA加速器之间的DMA带宽高达6.91 GBps(利用率86%),支持多达16通道且实现通道负载均衡,该设计有效支撑了国产FPGA异构加速器在数据中心场景下的规模化部署。 展开更多
关键词 pcie FPGA 异构加速 多通道 链式DMA
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基于Express框架的软件包管理系统的设计
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作者 刘凯 《电子制作》 2026年第1期103-106,共4页
为了共享代码实现软件复用的效果,提出了基于Express框架的软件包管理系统。以模块化架构为基础,采用B/S和C/S组合模式,通过Restful API实现前后端通信,以React框架实现前端,后端采用Express框架,通过元数据描述包信息并引入依赖解析算... 为了共享代码实现软件复用的效果,提出了基于Express框架的软件包管理系统。以模块化架构为基础,采用B/S和C/S组合模式,通过Restful API实现前后端通信,以React框架实现前端,后端采用Express框架,通过元数据描述包信息并引入依赖解析算法,确保软件安装的完整性与一致性。该系统分析了软件包管理系统的总体设计,系统运行的整个流程,前端与后端交互的RESTful API设计。系统实现了对用户的管理,软件包的发布、搜索、个人信息管理等功能。该系统已经处于初步运行阶段,已经成为企业软件管理的重要组成部分。 展开更多
关键词 软件包管理 express框架 模块化架构 软件包完整性校验
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Bioinformatics Identification of the Lipoxygenase Gene Family and Analysis of Their Gene Expression Characteristics in Physcomitrella Patens
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作者 Li LI Shan JIANG +1 位作者 Tianmin CHE Gang QIAO 《Asian Agricultural Research》 2026年第1期51-57,64,共8页
[Objectives]To investigate the structure and function of the lipoxygenase(LOX)gene family in Physcomitrella patens.[Methods]This study employed bioinformatics methods to identify and predict LOX gene family members.Qu... [Objectives]To investigate the structure and function of the lipoxygenase(LOX)gene family in Physcomitrella patens.[Methods]This study employed bioinformatics methods to identify and predict LOX gene family members.Quantitative real-time PCR(qRT-PCR)was utilized to analyze the expression patterns of LOX genes at different stages of Botrytis cinerea infection.[Results]The P.patens LOX gene family comprises eight putative proteins,including two 12-LOX-type members and six 13-LOX-type members.Among the eight LOX proteins,PpLOX7 exhibited the lowest molecular weight and shortest amino acid sequence.PpLOX7 was identified as a basic protein with an isoelectric point(pI)of 8.54,while all other members were acidic.Subcellular localization analysis indicated that PpLOX7 was localized to the chloroplast,whereas the remaining members were distributed in the cytoplasm.Secondary structure prediction showed that all eight proteins were predominantly composed of random coils andα-helixes.Chromosomal mapping revealed that the LOX genes were distributed across 7 of the 27 chromosomes in P.patens,with PpLOX1 and PpLOX2 tandemly arranged on chromosome 15.The qRT-PCR analysis demonstrated distinct expression patterns among the eight PpLOX genes following B.cinerea infection.PpLOX1-3 and PpLOX7 were upregulated to varying degrees,suggesting their potential involvement in the early defense response of P.patens against B.cinerea.Notably,PpLOX2 exhibited highly significant differential expression,making it a key candidate for further investigation.[Conclusions]This study provides foundational insights into the functional roles of the LOX gene family in P.patens during biotic stress responses. 展开更多
关键词 Physcomitrella patens LIPOXYGENASE BIOINFORMATICS Gene expression
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A machine learning-based depression recognition model integrating spiritexpression features from traditional Chinese medicine
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作者 Minghui Yao Rongrong Zhu +4 位作者 Peng Qian Huilin Liu Xirong Sun Limin Gao Fufeng Li 《Digital Chinese Medicine》 2026年第1期68-79,共12页
Objective To develop a depression recognition model by integrating the spirit-expression diagnostic framework of traditional Chinese medicine(TCM)with machine learning algorithms.The proposed model seeks to establish ... Objective To develop a depression recognition model by integrating the spirit-expression diagnostic framework of traditional Chinese medicine(TCM)with machine learning algorithms.The proposed model seeks to establish a TCM-informed tool for early depression screening,thereby bridging traditional diagnostic principles with modern computational approaches.Methods The study included patients with depression who visited the Shanghai Pudong New Area Mental Health Center from October 1,2022 to October 1,2023,as well as students and teachers from Shanghai University of Traditional Chinese Medicine during the same period as the healthy control group.Videos of 3–10 s were captured using a Xiaomi Pad 5,and the TCM spirit and expressions were determined by TCM experts(at least 3 out of 5 experts agreed to determine the category of TCM spirit and expressions).Basic information,facial images,and interview information were collected through a portable TCM intelligent analysis and diagnosis device,and facial diagnosis features were extracted using the Open CV computer vision library technology.Statistical analysis methods such as parametric and non-parametric tests were used to analyze the baseline data,TCM spirit and expression features,and facial diagnosis feature parameters of the two groups,to compare the differences in TCM spirit and expression and facial features.Five machine learning algorithms,including extreme gradient boosting(XGBoost),decision tree(DT),Bernoulli naive Bayes(BernoulliNB),support vector machine(SVM),and k-nearest neighbor(KNN)classification,were used to construct a depression recognition model based on the fusion of TCM spirit and expression features.The performance of the model was evaluated using metrics such as accuracy,precision,and the area under the receiver operating characteristic(ROC)curve(AUC).The model results were explained using the Shapley Additive exPlanations(SHAP).Results A total of 93 depression patients and 87 healthy individuals were ultimately included in this study.There was no statistically significant difference in the baseline characteristics between the two groups(P>0.05).The differences in the characteristics of the spirit and expressions in TCM and facial features between the two groups were shown as follows.(i)Quantispirit facial analysis revealed that depression patients exhibited significantly reduced facial spirit and luminance compared with healthy controls(P<0.05),with characteristic features such as sad expressions,facial erythema,and changes in the lip color ranging from erythematous to cyanotic.(ii)Depressed patients exhibited significantly lower values in facial complexion L,lip L,and a values,and gloss index,but higher values in facial complexion a and b,lip b,low gloss index,and matte index(all P<0.05).(iii)The results of multiple models show that the XGBoost-based depression recognition model,integrating the TCM“spirit-expression”diagnostic framework,achieved an accuracy of 98.61%and significantly outperformed four benchmark algorithms—DT,BernoulliNB,SVM,and KNN(P<0.01).(iv)The SHAP visualization results show that in the recognition model constructed by the XGBoost algorithm,the complexion b value,categories of facial spirit,high gloss index,low gloss index,categories of facial expression and texture features have significant contribution to the model.Conclusion This study demonstrates that integrating TCM spirit-expression diagnostic features with machine learning enables the construction of a high-precision depression detection model,offering a novel paradigm for objective depression diagnosis. 展开更多
关键词 Traditional Chinese medicine SPIRIT expressION Feature fusion DEPRESSION Recognition model
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Analysis ofβ-furanosidase Activity and Gene Expression in the Midgut of Fifth-instar Silkworm(Bombyx mori)Larvae
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作者 Weike YANG Changxiong HU +2 位作者 Qiongyan LI Zenghu LIU Fenfen TANG 《Agricultural Biotechnology》 2026年第1期1-4,共4页
[Objectives]The present study was conducted to investigate the change rule ofβ-fructofuranosidase gene expression and its enzyme activity in the midgut of 5 th instar silkworm(Bombyx mori),in order to provide a refer... [Objectives]The present study was conducted to investigate the change rule ofβ-fructofuranosidase gene expression and its enzyme activity in the midgut of 5 th instar silkworm(Bombyx mori),in order to provide a reference for illustrating the enzymatic mechanism of usingβ-fructofuranosidase to absorb sucrose nutrition from mulberry leaves.[Methods]Real-time fluorescent quantitative PCR was applied to analyze the expression of BmSuc1 and BmSuc2 in midgut of 5 th-instar silkworm larvae,meanwhile the activities ofβ-fructofuranosidase was determined.[Results]BmSuc1 was expressed in the midgut of 5 th-instar silkworm larvae at different developmental stages.Its expression was upregulated at the beginning of the 5 th instar and during the peak feeding period,whereas BmSuc2 expression remained very low throughout the entire 5 th instar.The activity ofβ-fructofuranosidase was relatively high during the peak feeding period of 5 th-instar larvae,showing a trend of increasing first and then decreasing.[Conclusions]The expression pattern of the BmSuc1 gene and the changes inβ-fructofuranosidase activity were generally consistent with the physiological process of sugar nutrient absorption and utilization from mulberry leaves in 5 th-instar silkworms.It suggests that BmSuc1,as a sucrose hydrolase gene,plays a major role in the digestion and absorption of sucrose nutrients from mulberry leaves in the midgut tissue. 展开更多
关键词 Bombyx mori Β-FRUCTOFURANOSIDASE BmSuc1 BmSuc2 Gene expression
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Genome-wide characterization and expression analysis of the cultivated peanut AhPR10 gene family mediating resistance to Aspergillus flavus
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作者 Qi Zhao Mengjie Cui +11 位作者 Tengda Guo Lei Shi Feiyan Qi Ziqi Sun Pei Du Hua Liu Yu Zhang Zheng Zheng Bingyan Huang Wenzhao Dong Suoyi Han Xinyou Zhang 《Journal of Integrative Agriculture》 2026年第1期56-67,共12页
The pathogenesis-related protein PR10 plays a vital role in plant growth,development,and stress responses.This study systematically identified and analyzed PR10 genes in cultivated peanut(Arachis hypogaea L.),examinin... The pathogenesis-related protein PR10 plays a vital role in plant growth,development,and stress responses.This study systematically identified and analyzed PR10 genes in cultivated peanut(Arachis hypogaea L.),examining their phylogenetic relationships,conserved motifs,gene structures,and syntenic relationships.The analysis identified 54 Ah PR10 genes,which were classified into eight groups based on phylogenetic relationships,supported by gene structure and conserved motif characterization.Analysis of chromosomal distribution and synteny demonstrated that segmental duplications played a crucial role in the expansion of the Ah PR10 gene family.The identified Ah PR10 genes exhibited both constitutive and inducible expression patterns.Significantly,Ah PR10-7,Ah PR10-33,and Ah PR10-41 demonstrated potential importance in peanut resistance to Aspergillus flavus.In vitro fungistatic experiments demonstrated that recombinant Ah PR10-33 effectively inhibited A.flavus mycelial growth.These findings provide valuable insights for future investigations into Ah PR10 functions in protecting peanut from A.flavus infection. 展开更多
关键词 cultivated peanut PR10 phylogenetic analysis expression pattern Aspergillus avus
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Expression level and spatial distribution of opsin gene in Oratosquilla oratoria compound eye
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作者 Fangrui LOU Xiaowen DUAN +2 位作者 Jiaoli ZHOU Yue DING Zhiqiang HAN 《Journal of Oceanology and Limnology》 2026年第1期340-356,共17页
Due to the unique microstructure and diverse opsin genes of the trinocular compound eye,stomatopoda possess an extraordinary ability to perceive multiple properties of light.They not only can detect natural light(NL)a... Due to the unique microstructure and diverse opsin genes of the trinocular compound eye,stomatopoda possess an extraordinary ability to perceive multiple properties of light.They not only can detect natural light(NL)and linearly polarized light(LPL),but also are the only animals capable of recognizing circularly polarized light(CPL).Here,we integrated single-cell RNA sequencing,previously published Illumina data,and in-situ hybridization(ISH)to quantify and localize functional opsin genes in Oratosquilla oratoria,a common stomatopoda species in the China Sea.A total of high-quality 31777 cells were captured for the first time in the O.oratoria compound eye,which were classified into 25 cell subpopulations,and hypothesized that cluster 22 is a critical cell subpopulation responsible for light(whether NL,LPL,or CPL)response in O.oratoria.Furthermore,we propose that the long-wavelengthsensitive opsin gene(lws)gene family,retinol dehydrogenase(rdh),voltage-gated ion channel(vgic),arrestin(arr),and myosin(myo)collectively mediate the light response in O.oratoria.Considering that very few vision-related opsin genes show differential expression in right-handed CPL(RCPL)-vs.-dark(DL),which provides additional evidence that stomatopoda cannot recognize RCPL.Meanwhile,we believe that UV-stimulated scaffold protein A(uvssa)and red pigment concentrating hormone(rpch)play special contributions in the left-handed CPL(LCPL)environment response.ISH revealing that 16 lws,6 middle-wavelength-sensitive(mws),and 2 ultraviolet(uv)opsin genes were expressed in the photoreceptors of the O.oratoria compound eye.Although the inability to determine the functional types of cell subpopulations limits the resolution of opsin genes,these findings systematically elucidate the specific expression patterns of opsin genes in O.oratoria and represent a significant step toward refining the visual ecological theory of O.oratoria and other stomatopod species. 展开更多
关键词 Oratosquilla oratoria opsin gene expression pattern single-cell RNA sequencing in-situ hybridization
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Unveiling cell-type-specific mode of evolution in comparative single-cell expression data
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作者 Tian Qin Hongju Zhang Zhengting Zou 《Journal of Genetics and Genomics》 2026年第1期28-42,共15页
While methodology for determining the mode of evolution in coding sequences has been well established,evaluation of adaptation events in emerging types of phenotype data needs further development.Here,we propose an an... While methodology for determining the mode of evolution in coding sequences has been well established,evaluation of adaptation events in emerging types of phenotype data needs further development.Here,we propose an analysis framework(expression variance decomposition,EVaDe)for comparative single-cell expression data based on phenotypic evolution theory.After decomposing the gene expression variance into separate components,we use two strategies to identify genes exhibiting large between-taxon expression divergence and small within-cell-type expression noise in certain cell types,attributing this pattern to putative adaptive evolution.In a dataset of primate prefrontal cortex,we find that such humanspecific key genes enrich with neurodevelopment-related functions,while most other genes exhibit neutral evolution patterns.Specific neuron types are found to harbor more of these key genes than other cell types,thus likely to have experienced more extensive adaptation.Reassuringly,at the molecular sequence level,the key genes are significantly associated with the rapidly evolving conserved non-coding elements.An additional case analysis comparing the naked mole-rat(NMR)with the mouse suggests that innateimmunity-related genes and cell types have undergone putative expression adaptation in NMR.Overall,the EVaDe framework may effectively probe adaptive evolution mode in single-cell expression data. 展开更多
关键词 Single-cell transcriptomics Gene expression Adaptive evolution Cell type Phenotypic evolution Prefrontal cortex Naked mole-rat
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Gap-free,haplotype-resolved genome assembly reveals allele-specific expression and fruit color regulation in coconut
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作者 Min Chen Jing Li +6 位作者 Ziqi Ye Xiwei Sun Xiaomei Liu Hao Ding Lixia Zhou Xingtan Zhang Yaodong Yang 《Horticultural Plant Journal》 2026年第1期217-220,共4页
Coconut(Cocos nucifera L.),a major oil and fruit crop of the Arecaceae family,is extensively cultivated across the Asia—Pacific region.Despite its agricultural importance,genome assembly in coconut remains challengin... Coconut(Cocos nucifera L.),a major oil and fruit crop of the Arecaceae family,is extensively cultivated across the Asia—Pacific region.Despite its agricultural importance,genome assembly in coconut remains challenging due to its large genome size and high proportion of repetitive sequences.Allele-specific expression(ASE)plays a key role in regulating plant development and evolution,yet research on ASE in coconut is limited(Shao et al.,2019;Li et al.,2021;Zhang et al.,2021;Hu et al.,2022).Among phenotypic traits,fruit color is especially important as an indicator of maturity,guiding harvest timing and post-harvest processes(Kapoor et al.,2022).While prior studies have explored various coconut traits such as salt tolerance,fiber content,and plant height(Wang et al.,2021;Yang et al.,2021),investigations into ASE and fruit color remain scarce. 展开更多
关键词 allele specific expression Cocos nucifera haplotype resolved fruit color Asia Pacific region COCONUT phenotypic trai oil fruit crop
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Prognostic Significance of DNA Repair Gene mRNA Expression in Early-Stage Breast Cancer:Insights into Clinical Relevance
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作者 Ina Shehaj Slavomir Krajnak +7 位作者 Katrin Almstedt Yaman Degirmenci Roxana Schwab Kathrin Stewen Walburgis Brenner Annette Hasenburg Marcus Schmidt Anne-Sophie Heimes 《Oncology Research》 2026年第3期365-386,共22页
The prognostic and therapeutic roles of biological markers in early-stage breast cancer(eBC)warrant further investigation.Non-Breast Cancer(BRCA)genes,along with moderate-and low-penetrance breast cancer risk variant ... The prognostic and therapeutic roles of biological markers in early-stage breast cancer(eBC)warrant further investigation.Non-Breast Cancer(BRCA)genes,along with moderate-and low-penetrance breast cancer risk variant genes,are crucial formaintaining genome stability,yet their prognostic significance in eBCremains unclear.This study aimed to evaluate the impact of non-BRCA genes on clinical outcomes in eBC patients.Significant correlations were observed between the messenger ribonucleic acid(mRNA)expression levels of the genes Ataxia-telangiectasia mutated(ATM),Bloom helicase gene(BLM),and WRN RecQ Like Helicase(WRN)and patient prognosis.High mRNA expression of ATM was associated with longer metastasis-free survival(MFS).Conversely,lower mRNA expression of BLM correlated with favorable outcomes,particularly in triple-negative tumors.Additionally,high levels of WRN mRNA expression were linked to significantly longer MFS compared to low expression levels.This study highlights the prognostic significance of ATM,BLM,and WRN in predicting survival outcomes in eBC patients.Background:The prognostic significance of various biological and non-BRCA genetic in early-stage breast cancer(eBC)remains unclear and warrants further investigation.This study therefore aimed to evaluate the prognostic impact of these genes on clinical outcomes in breast cancer.Methods:Patients included in this study were subdivided into two groups based on low and high messenger ribonucleic acid(mRNA)expression levels.Statistical analysis,including Kaplan-Meier curves,univariable,andmultivariable Cox regression analyses,was performed to assess metastasis-free survival(MFS)of mRNA expression of non-BRCA genes.Subgroup analyses were also conducted among four different molecular subtypes of eBC.Results:Our analysis revealed significant correlations between mRNA-expression levels of Ataxiatelangiectasia mutated(ATM),Bloom helicase gene(BLM),and WRN RecQ Like Helicase(WRN)and patient prognosis.High mRNA expression of ATM correlated with longer MFS in the entire cohort(p=0.022,Log Rank),and in luminal-B-like tumors(p=0.036).Lower mRNA expression of BLM was associated with favorable outcomes(p=0.011,Log Rank),particularly in triple-negative eBC(p=0.030,Log Rank).Finally,high levels of WRN mRNA expression correlated with significantly longerMFS compared to lowmRNA expression levels(p=0.009,Log Rank).Conclusions:This study underscores the prognostic significance of moderate penetrance breast cancer risk variant genes,such as ATM,BLM,and WRN,for survival outcomes in eBC. 展开更多
关键词 Ataxia-telangiectasia mutated(ATM) Bloom helicase gene(BLM) WRN RecQ Like Helicase(WRN) breast cancer(BC) gene expression analyses survival
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基于PCIExpress的高速红外图像采集系统 被引量:6
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作者 兰春嘉 汤心溢 +1 位作者 王世勇 黎绍秀 《红外技术》 CSCD 北大核心 2011年第1期37-40,共4页
介绍了一种基于PCI Express(PCI-E)总线的高速红外图像采集系统。重点介绍了PCI-E图像采集板卡的硬件设计和主机的软件设计,PCI-E图像采集板卡采用了基于FPGA的硬件结构,主机的软件设计包括驱动程序和应用程序两部分。经实验测试,此高... 介绍了一种基于PCI Express(PCI-E)总线的高速红外图像采集系统。重点介绍了PCI-E图像采集板卡的硬件设计和主机的软件设计,PCI-E图像采集板卡采用了基于FPGA的硬件结构,主机的软件设计包括驱动程序和应用程序两部分。经实验测试,此高速红外图像采集系统能完成红外图像的实时采集、显示及存储,性能稳定可靠。系统适用于高帧频、大数据量的红外图像实时采集。 展开更多
关键词 红外图像 采集系统 PCI express FPGA
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PCIExpress接口时钟产生电路的设计与实现 被引量:1
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作者 朱全庆 张道礼 +1 位作者 沈绪榜 李海华 《电子工程师》 2005年第6期10-12,共3页
介绍了PCIExpress接口时钟产生电路的设计,包括体系结构设计、系统设计与仿真、电路设计与仿真、版图设计。该时钟产生电路经过TSMC0.13μm1P8MCMOS工艺验证,工作电压为1.5V。结果表明该时钟产生电路能够满足PCIExpress接口的要求。
关键词 时钟产生电路 锁相环 压控振荡器 PCI express接口
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一种高性能PCIe接口设计与实现
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作者 张梅娟 辛昆鹏 周迁 《现代电子技术》 北大核心 2025年第8期70-74,共5页
多款处理器在PCIe 2.0×4下传输速率不足理论带宽的20%,最高仅有380 MB/s,不能满足实际应用需求。为解决嵌入式处理器PCIe接口传输速率过低的问题,设计一款高性能PCIe接口,有效提高了接口数据传输速率。经性能瓶颈系统分析,增加设计... 多款处理器在PCIe 2.0×4下传输速率不足理论带宽的20%,最高仅有380 MB/s,不能满足实际应用需求。为解决嵌入式处理器PCIe接口传输速率过低的问题,设计一款高性能PCIe接口,有效提高了接口数据传输速率。经性能瓶颈系统分析,增加设计PCIe DMA与处理器Cache一致性功能,能解决DMA传输完成后软件Cache同步耗时严重的问题,使速率提升3.8倍,达到1 450 MB/s。在硬件设计上DMA支持链表模式,通过描述符链表将分散的内存集聚起来,一次DMA启动可完成多个非连续地址内存的数据传输,并优化与改进软件驱动中分散集聚DMA实现方式,充分利用硬件Cache一致性功能,进一步提升10%的传输速率,最终达到PCIe 2.0×4理论带宽的80%。此外,该PCIe接口采用多通道DMA的设计,最大支持8路独立DMA读写通道,可应用于多核多任务并行传输数据的应用场景,更进一步提升整体数据传输带宽。经验证,该PCIe接口具有良好的稳定性和高效性,最大可支持8通道数据并行传输,且单通道传输速率可达到理论速率的80%。 展开更多
关键词 pcie接口 DMA控制器 高速数据传输 CACHE一致性 多通道设计 分散集聚 链表模式
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加权轮询策略的PCIExpress DMA控制器的设计与实现 被引量:3
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作者 崔骞 高小鹏 龙翔 《微计算机信息》 2010年第23期148-150,共3页
针对目前PCIExpress桥接芯片在全双工模式下不能很好地解决收发传输平衡的问题,提出了基于加权循环分时技术的DMA控制器。通过对Burst传输的分析,从体系结构和指令集两个层面阐述了片上DMA控制器设计的意义及价值,给出了加权循环分时技... 针对目前PCIExpress桥接芯片在全双工模式下不能很好地解决收发传输平衡的问题,提出了基于加权循环分时技术的DMA控制器。通过对Burst传输的分析,从体系结构和指令集两个层面阐述了片上DMA控制器设计的意义及价值,给出了加权循环分时技术的一种实现。对传输卡的测试实验显示,针对不同传输需求利用不同的轮询权重值对分时策略进行优化,最高能够获得37倍的加速比。 展开更多
关键词 PCI express 加权循环 Burst传输 DMA
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嵌入式异构智能计算系统的PCIe总线传输带宽优化 被引量:1
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作者 喻绪邦 吴济文 +2 位作者 夏宏 莫昊 赵二虎 《计算机应用》 北大核心 2025年第9期2913-2918,共6页
近年来随着人工智能(AI)技术的发展,深度学习算法和专用AI处理器芯片已日益广泛地应用于边缘端和物端数据信号处理系统,如何在赋能系统高智能计算能力的同时,实现异构处理器之间高带宽、低延时的数据传输,已成为亟须解决的核心技术之一... 近年来随着人工智能(AI)技术的发展,深度学习算法和专用AI处理器芯片已日益广泛地应用于边缘端和物端数据信号处理系统,如何在赋能系统高智能计算能力的同时,实现异构处理器之间高带宽、低延时的数据传输,已成为亟须解决的核心技术之一。因此,设计一种集成寒武纪MLU220芯片、国产飞腾FT2000/4型CPU和Xilinx XC7K325T现场可编程门阵列(FPGA)的嵌入式异构智能计算系统,系统异构处理器之间采用PCIe(Peripheral Component Interconnect express)总线实现高速互联与数据传输。此外,提出一种Linux下的PCIe总线Scatter-Gather DMA(Direct Memory Access)传输优化技术,通过基于双缓冲的预取技术和基于工作队列的中断处理,有效提高CPU与FPGA异构处理器之间的PCIe总线数据传输带宽。系统图像传输测试结果表明,CPU与FPGA异构处理器之间的PCIe2.0 X4总线传输10张2048×1024灰度图像数据时,所提系统在DMA双通道上的读写速率分别达到了1610 MB/s和1655 MB/s,为PCIe2.0 X4总线理论带宽值的81%和83%,验证了所设计系统的实用性和先进性。 展开更多
关键词 pcie总线 异构计算系统 Scatter-Gather DMA DMA多通道 图像传输
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基于VirtIO和Qemu的PCIE卡虚拟化
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作者 解永亮 彭琦 付国楷 《数字技术与应用》 2025年第3期52-55,共4页
为了满足普通PCIE卡在虚拟化环境中多客户机同时访问的功能需求,通过对Linux中基于内核的虚拟机子系统、半虚拟化子系统及快速模拟器的研究,本文提出了一种在Linux系统中具备良好兼容性、灵活性和通用性的普通PCIE卡模拟机制,并详细描... 为了满足普通PCIE卡在虚拟化环境中多客户机同时访问的功能需求,通过对Linux中基于内核的虚拟机子系统、半虚拟化子系统及快速模拟器的研究,本文提出了一种在Linux系统中具备良好兼容性、灵活性和通用性的普通PCIE卡模拟机制,并详细描述了其工作原理、软件模块组成、实现要点和技术优势,最后在实际环境中对该方案进行了测试,并对其应用和部署方式提出了一些建议。 展开更多
关键词 快速模拟器 QEMU VirtIO LINUX系统 pcie卡虚拟化
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基于FPGA的PCIe接口DMA数据传输设计
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作者 任勇峰 赵清琳 《舰船电子工程》 2025年第10期67-70,共4页
为解决高速数据传输中高带宽的要求,设计一种基于PCIe接口的数据传输系统。该系统通过PCIe接口实现FPGA与CPU的互联,采用光模块实现外部RapidIO模块数据与FPGA进行通信,通过设计顶层DMA传输架构,将数据通过PCIe接口上传至CPU的DDR。此... 为解决高速数据传输中高带宽的要求,设计一种基于PCIe接口的数据传输系统。该系统通过PCIe接口实现FPGA与CPU的互联,采用光模块实现外部RapidIO模块数据与FPGA进行通信,通过设计顶层DMA传输架构,将数据通过PCIe接口上传至CPU的DDR。此外介绍了PCIe硬件设计与初始化训练过程,详细分析了DMA数据传输模块中数据读写方式和状态转换流程,同时多FIFO设计可扩展多通道数据传输,在现有硬件链路的基础上最大化实现数据高速传输。 展开更多
关键词 PCI express FPGA DMA DDR 数据传输
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基于UVM的PCIe交换芯片Switch子系统验证平台的设计 被引量:1
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作者 郑锐 沈剑良 +2 位作者 刘冬培 李智超 曹睿 《计算机应用研究》 北大核心 2025年第5期1480-1489,共10页
PCIe是一种高速串行计算机扩展总线标准,据此设计的PCIe交换芯片可将CPU提供的PCIe通道扩展出更多的PCIe接口。然而,随着PCIe交换芯片设计复杂度和验证向量剧增,传统基于Verilog搭建的验证平台难以实现对逻辑复杂的Switch子系统高效地验... PCIe是一种高速串行计算机扩展总线标准,据此设计的PCIe交换芯片可将CPU提供的PCIe通道扩展出更多的PCIe接口。然而,随着PCIe交换芯片设计复杂度和验证向量剧增,传统基于Verilog搭建的验证平台难以实现对逻辑复杂的Switch子系统高效地验证,且缺乏功能覆盖率模型。为解决上述问题,采用UVM通用验证方法学,搭建了针对PCIe交换芯片中Switch子系统的验证平台,采用层次划分设计,支持覆盖率驱动,且较于一般UVM验证平台作出效率优化。具体而言,首先,对平台组件Reference Model建立通信对象和通信方式进行优化设计;其次,对平台组件ScoreBoard的比对方式和接收报文端口进行改进;最后,依据PCIe协议及交换芯片特点,对功能点进行梳理分类后针对性地设计了测试用例,对Switch子系统进行全面验证。经信号波形及覆盖率数据的分析表明,改进后的验证平台在没有人为过滤的情况下实现了96.8%的代码覆盖率和100%的功能覆盖率,仿真时间平均减少了约10%。该平台显著提升了验证效率,高效地支撑了PCIe交换芯片的验证工作,为相关UVM验证平台的搭建提供了参考。 展开更多
关键词 pcie交换芯片 Switch子系统 UVM验证平台 reference model ScoreBoard 覆盖率
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基于FPGA的PCIExpress总线的DMA数据传输设计 被引量:1
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作者 姚明超 《电子技术与软件工程》 2016年第4期167-167,共1页
本设计通过使用Xilinx公司FPGA的PCIe IP硬核的系统带宽大、传输速率快、扩展性高等特点设计基于PCIe总线的高速DMA传输的数据通道平台。DMA的读和写传输带宽分别可以达到750MB/s和850MB/s。
关键词 FPGA pcie总线 直接内存读取 赛灵思
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