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MART(Splitting-Merging Assisted Reliable)Independent Component Analysis for Extracting Accurate Brain Functional Networks

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Neuroscience Bulletin 2024年第7期40卷 905-920页

作者： Xingyu He Vince D.Calhoun yuhui du School of Computer and Information Technology Shanxi UniversityTaiyuan 030006China Tri-Institutional Center for Translational Research in Neuroimaging and Data Science Georgia State UniversityGeorgia Institute of TechnologyEmory UniversityAtlanta 30303USA

Functional networks(FNs)hold significant promise in understanding brain *** component analysis(ICA)has been applied in estimating FNs from functional magnetic resonance imaging(fMRI).However,determining an optimal model order for ICA remains challenging,leading to criticism about the reliability of FN ***,we propose a SMART(splitting-merging assisted reliable)ICA method that automatically extracts reliable FNs by clustering independent components(ICs)obtained from multi-model-order ICA using a simplified graph while providing linkages among FNs deduced from different-model *** extend SMART ICA to multi-subject fMRI analysis,validating its effectiveness using simulated and real fMRI *** on simulated data,the method accurately estimates both group-common and group-unique components and demonstrates robustness to *** two age-matched cohorts of resting fMRI data comprising 1,950 healthy subjects,the resulting reliable group-level FNs are greatly similar between the two cohorts,and interestingly the subject-specific FNs show progressive changes while age ***,both small-scale and large-scale brain FN templates are provided as benchmarks for future *** together,SMART ICA can automatically obtain reliable FNs in analyzing multi-subject fMRI data,while also providing linkages between different FNs.

关键词： Independent component analysis Functional magnetic resonance imaging-Brain functional networks Clustering Multi-model-order

The Dynamic Functional Network Connectivity Analysis Framework

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Engineering 2019年第2期5卷 190-193页

作者： Zening Fu yuhui du Vince D. Calhoun The Mind Research Network Albuquerque NM 87106 USA School of Computer and Information Technology Shanxi University Taiyuan 030006 China Department of Electrical and Computer Engineering University of New Mexico Albuquerque NM 87131 USA

1. Overview The human brain is a highly dynamic system with time-varying neural activity and rapidly changing neural integration [1–3]. Research using high-temporal-resolution imaging techniques (such as electroencephalography, EEG) has identified reoccurring microstates (by characterizing changes in the power of brain activity)[4,5], which are related to spontaneous thoughts and mental processes [6].

关键词： Overview The human highly dynamic mental processes

Enhanced microwave absorption at low frequency of superparamagnetic Fe3O4 single nano-crystals

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Enhanced microwave absorption at low frequency of superparam...

“行业创新大会”暨协会六届十次常务理事会

作者： ZongJie Yin yuhui du Lin Yang Guangzhou Special Pressure Equipment Inspection and Research Institute

The superparamagnetic Fe O single nanocrystals with diameters of 10-15 nm have been synthesized via a simple method. Several characterizations such as SEM, TEM and XRD are used to obtain the morphology and crystallinity of Fe O nanoparticles. The investigation about wave absorption property indicates that Fe O nanocrystals is an excellent absorber, the effective frequency band(RL<-5.30 dB) of absorbers are obtained in a broad frequency range from 2.0 GHz to 15.40 GHz and the minimum reflection losses and the peak frequencies are-10.5 dB and-7.7 dB at the frequency of 10.4 GHz and 14.1 GHz, respectively.

关键词： Fe3O4 single nanocrystals wave absorption property

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Taussky定理推广与应用

应用数学学报 2000年第1期23卷 76-81页

作者：杜宇辉北华大学师范学院数理系吉林市132013

本文在Ｃａｓｓｉｎｉ卵形域上推广了Ｔａｕｓｓｋｙ定理，所得结果修正了Ｂｒａｕｅｒ定理．作为应用给出不可约双对角占优矩阵非奇异的充要条件．最后把基本结果推广到分块矩阵上。

关键词： Tausskey定理不可约矩阵双对角占优矩阵

发掘精神分裂症大脑连接变异的集成聚类动态功能连接分析方法

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中国生物医学工程学报 2024年第3期43卷 257-266页

作者：方嵩柯杜宇慧山西大学计算机与信息技术学院太原030006

近年来,基于功能磁共振成像的动态功能连接在研究精神疾病方面表现出巨大的潜力。传统的基于聚类的动态功能连接分析方法(如K-means)受到类别个数、初始值和噪声的影响可能导致不可靠的功能连接状态(FCSs)。本研究提出了一种新的集成聚... 详细信息

近年来,基于功能磁共振成像的动态功能连接在研究精神疾病方面表现出巨大的潜力。传统的基于聚类的动态功能连接分析方法(如K-means)受到类别个数、初始值和噪声的影响可能导致不可靠的功能连接状态(FCSs)。本研究提出了一种新的集成聚类动态功能连接分析方法。首先,利用多个不同的类别个数(k值)进行K-means产生多样性的簇;然后,基于Jaccard系数和随机游走挖掘不同簇之间的相似性以构造反应簇间关系的加权图;最终,对加权图进行社区检测获得可靠的元簇,并通过投票的方式将每个功能连接窗口分组到不同的元簇中,计算其质心作为功能连接状态。基于105名健康对照(HC)和70名精神分裂症(SZ)患者的fMRI数据,全方位比较所提出的方法和常用的基于K-means的方法进行动态功能网络分析的效果。相较于K-means方法,所提出方法在FCS 2上的平均类间相似性由83.2%降低至81.1%,在FCS 3上的平均类间相似性由76.8%降低至73.5%,聚类评估指标Davies Bouldin指数由6.74降低至6.44,Silhouette Coefficient指数由0.018提高至0.031。显示HC和SZ组的组间差异更集中于FCS 2,而K-means方法的组间差异分散在FCS 2、FCS 3和FCS 4。所提出方法可以自动获得FCSs数目,并具有更好的聚类质量和更可靠的功能连接状态,还发现了比K-means更有意义的组间差异,支持了该方法在探索精神疾病生物标志物方面的应用潜力。

关键词：功能磁共振成像动态功能连接集成聚类 K-means聚类精神分裂症

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树脂再生废液中和处理的计算与设计

工业水处理 2005年第10期25卷 55-58页

作者：杜玉辉杨麟广州市锅炉压力容器监察检验所广东广州510080

对除盐系统酸、碱再生废液的中和处理的计算公式进行了推导,用理论分析和数理推导的方法,证明了除盐系统酸、碱再生废液混合后仍显酸性,并以此提出了再生废液中和处理新工艺,设计了新颖实用、符合环保要求的处理方案。

关键词：酸碱再生废液中和处理喷射器

低活性矿渣内养护水泥砂浆自收缩与电阻率的关系

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土木与环境工程学报（中英文） 2023年第6期45卷 173-179页

作者：杜玉会李双喜新疆农业大学水利与土木工程学院新疆水利工程安全与水灾害防治重点实验室乌鲁木齐830052

以预吸水低活性矿渣替代细集料作为内养护材料,研究低活性矿渣内养护砂浆自收缩与电阻率的变化规律,揭示两者的关系。结果表明:随着低活性矿渣掺量的增加,砂浆早期强度降低幅度大,随着龄期的延长,砂浆中后期强度降低幅度小于早期,建议... 详细信息

以预吸水低活性矿渣替代细集料作为内养护材料,研究低活性矿渣内养护砂浆自收缩与电阻率的变化规律,揭示两者的关系。结果表明:随着低活性矿渣掺量的增加,砂浆早期强度降低幅度大,随着龄期的延长,砂浆中后期强度降低幅度小于早期,建议低活性矿渣的合适掺量取为细集料质量的15%~25%;低活性矿渣内养护对砂浆电阻率发展影响明显,凝结硬化前,浆体电阻率随低活性矿渣掺量的增大而增大;凝结硬化后,浆体电阻率随低活性矿渣掺量的增大而减小;低活性矿渣内养护能有效抑制浆体各阶段的自收缩,尤其在快速收缩阶段和短暂膨胀阶段作用最为明显,同时,36 h龄期后电阻率与自收缩有很好的对应关系,可通过电阻率发展趋势预测自收缩的变化情况。

关键词：水泥砂浆内养护自收缩电阻率低活性矿渣

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Do methylenetetrahydrofolate dehydrogenase, cyclohydrolase, and formyltetrahydrofolate synthetase 1 polymorphisms modify changes in intelligence of school-age children in areas of endemic fluorosis?

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Chinese Medical Journal 2022年第15期135卷 1846-1854页

作者： Zichen Feng Ning An Fangfang Yu Jun Ma Na Li yuhui du Meng Guo Kaihong Xu Xiangbo Hou Zhiyuan Li Guoyu Zhou Yue Ba Department of Occupational and Environmental Health School of Public HealthZhengzhou UniversityZhengzhouHenan 450001China Department of Endemic Disease Kaifeng Center for Disease Control and PreventionKaifengHenan 475004China Dietary Center Zhengzhou Health Vocational CllegeZhengzhouHenan 450122China

Background: Excessive exposure to fluoride can reduce intelligence. Methylenetetrahydrofolate dehydrogenase, cyclohydrolase, and formyltetrahydrofolate synthetase 1 (MTHFD1) polymorphisms have important roles in neurodevelopment. However, the association ofMTHFD1 polymorphisms with children’s intelligence changes in endemic fluorosis areas has been rarely ***: A cross-sectional study was conducted in four randomly selected primary schools in Tongxu County, Henan Province, from April to May in 2017. A total of 694 children aged 8 to 12 years were included in the study with the recruitment by the cluster sampling method. Urinary fluoride (UF) and urinary creatinine were separately determined using the fluoride ion-selective electrode and creatinine assay kit. Children were classified as the high fluoride group and control group according to the median of urinary creatinine-adjusted urinary fluoride (UFCr) level. Four loci ofMTHFD1 were genotyped, and the Combined Raven’s Test was used to evaluate children’s intelligence quotient (IQ). Generalized linear model and multinomial logistic regression model were performed to analyze the associations between children’s UFCr level,MTHFD1 polymorphisms, and intelligence. The general linear model was used to explore the effects of gene-environment and gene-gene interaction on ***: In the high fluoride group, children’s IQ scores decreased by 2.502 when the UFCr level increased by 1.0 mg/L (β= –2.502, 95% confidence interval [CI]: –4.411, –0.593), and the possibility for having "excellent" intelligence decreased by 46.3% (odds ratio = 0.537, 95% CI: 0.290, 0.994). Children with the GG genotype showed increased IQ scores than those with the AA genotype of rs11627387 locus in the high fluoride group (P < 0.05). Interactions between fluoride exposure andMTHFD1 polymorphisms on intelligence were observed (Pinteraction < 0.05).Conclusion: Our findings suggest that excessive fluoride exposure may have adve

关键词： Fluoride Intelligence Interaction MTHFD1 gene

面向脑核磁共振识别运动任务的门控循环单元方法

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中国图象图形学报 2023年第2期28卷 589-600页

作者：袁振侯玉亮杜宇慧山西大学计算机与信息技术学院太原030006

目的在脑科学领域,已有研究借助脑功能核磁共振影像数据(functional magnetic resonance imaging,fMRI)探索和区分人类大脑在不同运动任务下的状态,然而传统方法没有充分利用fMRI数据的时序特性。对此,本文提出基于fMRI数据计算的全脑... 详细信息

目的在脑科学领域,已有研究借助脑功能核磁共振影像数据(functional magnetic resonance imaging,fMRI)探索和区分人类大脑在不同运动任务下的状态,然而传统方法没有充分利用fMRI数据的时序特性。对此,本文提出基于fMRI数据计算的全脑脑区时间信号(time course,TC)的门控循环单元(gated recurrent unit,GRU)方法(TC-GRU)进行运动任务分类。方法基于HCP(human connectome project)数据集中的100个健康被试者在5种运动任务中分两轮采集的1000条fMRI数据,对每种运动任务计算每个被试者在各脑区(共360个脑区)的时间信号;使用10折交叉验证方案基于训练集和验证集训练TC-GRU模型,并用构建好的模型对测试集进行测试,考察其对5种运动任务的分类能力,其中TC-GRU在各时刻的输入特征为全脑脑区在对应时刻的TC信号幅值,通过这样的方式提取全脑脑区在整个时间段的时序特征。同时,为了展示使用TC-GRU模型可挖掘fMRI数据中更丰富的信息,设计了多个对比实验进行比较,利用长短期记忆网络(long short-term memory,LSTM)、图卷积网络(graph convolutional network,GCN)和多层感知器(multi-layer perceptron,MLP)基于全脑脑区时间信号进行运动任务分类,以及利用MLP基于由fMRI数据估计的脑功能连接进行运动任务分类。此外,考察了先验的特征选择对分类效果的效应。结果基于全脑脑区时间信号的TC-GRU模型在运动任务中的分类准确率最高,为94.51%±2.4%,其次是基于全脑脑区时间信号的LSTM模型,准确率为93.73%±2.67%。基于全脑脑区时间信号利用MLP进行分类,有先验和无先验的特征选择准确率分别为92.75%±2.59%和92.04%±7.15%,比基于全脑脑区时间信号的GCN(准确率为87.14%±3.73%)和基于脑功能连接利用MLP进行分类(有先验和无先验的特征选择准确率分别为72.47%±4.47%和61.49%±9.97%)表现更好。结论TC-GRU模型可挖掘脑fMRI数据中丰富的时序信息,非常有效地对不同的运动任务进行分类。

关键词：脑功能核磁共振成像全脑脑区时间信号功能连接门控循环单元(GRU) 多层感知器(MLP) 运动任务分类