人脑活动是在秒级与毫秒级动态变化的,因此采用静态连接方式构建的功能性脑网络,会造成部分与时间相关有效特征的缺失。该文旨在研究情绪变化期间不同大脑区域之间相互作用的时空变化,提出了一个系统的分析框架。该框架包括相关性度量,...人脑活动是在秒级与毫秒级动态变化的,因此采用静态连接方式构建的功能性脑网络,会造成部分与时间相关有效特征的缺失。该文旨在研究情绪变化期间不同大脑区域之间相互作用的时空变化,提出了一个系统的分析框架。该框架包括相关性度量,脑状态分割,代表性时间片段提取以及动态网络构建和分析。首先,利用皮尔逊相关系数量化不同脑区之间的功能连通性。其次,计算两相邻时间点的相关性矩阵之间的奇异值分解(singular value decomposition, SVD)矢量空间距离,确定情绪转换点并对非平稳脑状态进行时间片分割,提取代表性时间片段。最后,基于相关性和频带功率分布构建不同网络模式,利用滑动窗口法估计动态相关模式和动态功率分布变化,然后提取脑动力学的多变量特征并进行分类识别。在SEED数据集上进行的相关实验验证了基于动态功能连接的情感评估方法的可行性,为不同情绪状态下建立脑动态模型开辟了新的途径。展开更多
Brassica rapa(AA,2n=20)and Raphanus sativus(RR,2n=18)are popular vegetables containing multiple secondary metabolites,such as flavonoids and anthocyanins.Nevertheless,fewstudies on miRNA expression profiles and potent...Brassica rapa(AA,2n=20)and Raphanus sativus(RR,2n=18)are popular vegetables containing multiple secondary metabolites,such as flavonoids and anthocyanins.Nevertheless,fewstudies on miRNA expression profiles and potential regulatory network of flavonoid metabolism have been reported in the intergeneric hybrid of B.rapa and R.sativus(Brassicacoraphanus,AARR,2n=38).Here,themiRNAs of Brassicacoraphanus and its parents were first identified by small RNA sequencing.It was revealed that 315 conserved miRNAs and 193 novel miRNAs were found in Brassicacoraphanus and its parents.Moreover,the miRNA expression profiles were characterized and 204 miRNAs with differential expression were obtained.Further analysis showed that 184 miRNAs were non-additively expressed in Brassicacoraphanus.At last,the potential regulatory network of flavonoid metabolism in Brassicacoraphanus was analyzed by multi-omics data,suggesting possible roles of miR858a and miR157a in regulating flavonoid synthesis pathway in Brassicacoraphanus.Taken together,this study provides useful resources for probing globalmiRNA expression patterns in Brassicacoraphanus,which facilitates regulatory mechanism research on the biosynthesis pathway of secondary metabolites in Brassicacoraphanus.展开更多
The failure types in gear systems vary,with typical ones mainly including pitting,cracking,wear,and broken teeth.Different modeling and stiffness calculation methods have been developed for various gear failure types....The failure types in gear systems vary,with typical ones mainly including pitting,cracking,wear,and broken teeth.Different modeling and stiffness calculation methods have been developed for various gear failure types.A unified method for typical gear failure modeling and stiffness calculation is introduced in this study by considering the deviations in the time-varying meshing stiffness(TVMS)of faulty gears resulting from the use of different methods.Specifically,a gear tooth is discretized into a large number of microelements expressed with a matrix,and unified models of typical gear failures are built by adjusting the values of the matrix microelements.The values and positions of the microelements in the tooth failure model matrix have the same physical meaning as the parameter variables in the potential energy method(PEM),so the matrix-based failure model can be perfectly matched with PEM.Afterward,a unified method for TVMS is established.Modeling of healthy and faulty gears with pitting,wear,crack,and broken tooth is performed with the matrix equation,and the corresponding TVMS values are calculated by incorporating the matrix models with PEM.On the basis of the results,the mechanism of typical fault types that affect TVMS is analyzed,and the conclusions are verified through the finite element method.The developed unified method is a promising technique for studying the dynamic response characteristics of gear systems with different failure types because of its superiority in eliminating stiffness deviations.展开更多
运用网络药理学方法探究黄连解毒汤调节巨噬细胞炎症反应、糖酵解、鞘脂代谢和谷氨酰胺代谢等方面的多成分、多靶点、多通路的相互作用规律和调控网络,为创新药物研究奠定基础。通过TCMSP数据库筛选黄连解毒汤活性成分, PharmMapper数...运用网络药理学方法探究黄连解毒汤调节巨噬细胞炎症反应、糖酵解、鞘脂代谢和谷氨酰胺代谢等方面的多成分、多靶点、多通路的相互作用规律和调控网络,为创新药物研究奠定基础。通过TCMSP数据库筛选黄连解毒汤活性成分, PharmMapper数据库预测靶点蛋白, DAVID数据库进行通路注释和分析, Cytoscape 3.2.1软件构建"活性成分-靶点-通路"网络图, GENEMANIA数据库进行蛋白相互作用分析, Systems Dock Web Site数据库进行分子对接验证。预测结果表明,黄连解毒汤中共筛选出84个活性成分,作用靶点111个,其中与巨噬细胞炎症相关的靶点蛋白13个,涉及代谢通路14条;与糖酵解、鞘脂代谢、谷氨酰胺代谢相关的靶点蛋白34个,涉及代谢通路8条。炎症相关蛋白和代谢相关蛋白通过物理相关性、蛋白共表达等方式互相作用,小檗碱、黄芩苷和栀子苷与5个重要靶点均能较好结合。黄连解毒汤可能通过作用于糖酵解、鞘脂代谢和谷氨酰胺代谢的相关靶点,影响其代谢过程中的代谢产物和酶,从而调节巨噬细胞炎症反应。展开更多
文摘人脑活动是在秒级与毫秒级动态变化的,因此采用静态连接方式构建的功能性脑网络,会造成部分与时间相关有效特征的缺失。该文旨在研究情绪变化期间不同大脑区域之间相互作用的时空变化,提出了一个系统的分析框架。该框架包括相关性度量,脑状态分割,代表性时间片段提取以及动态网络构建和分析。首先,利用皮尔逊相关系数量化不同脑区之间的功能连通性。其次,计算两相邻时间点的相关性矩阵之间的奇异值分解(singular value decomposition, SVD)矢量空间距离,确定情绪转换点并对非平稳脑状态进行时间片分割,提取代表性时间片段。最后,基于相关性和频带功率分布构建不同网络模式,利用滑动窗口法估计动态相关模式和动态功率分布变化,然后提取脑动力学的多变量特征并进行分类识别。在SEED数据集上进行的相关实验验证了基于动态功能连接的情感评估方法的可行性,为不同情绪状态下建立脑动态模型开辟了新的途径。
基金This research was funded by National key research and Development Program(Grant No.2017YFD0101701)the New Century Talents Support Program by the Ministry of Education of China(Grant No.NCET110172)the Natural Science Foundation of Hubei Province,China(Grant No.2019CFB476).We would like to thank Prof.Chuang Ma(Northwest A&F University)for helping to analyze the sequencing data.
文摘Brassica rapa(AA,2n=20)and Raphanus sativus(RR,2n=18)are popular vegetables containing multiple secondary metabolites,such as flavonoids and anthocyanins.Nevertheless,fewstudies on miRNA expression profiles and potential regulatory network of flavonoid metabolism have been reported in the intergeneric hybrid of B.rapa and R.sativus(Brassicacoraphanus,AARR,2n=38).Here,themiRNAs of Brassicacoraphanus and its parents were first identified by small RNA sequencing.It was revealed that 315 conserved miRNAs and 193 novel miRNAs were found in Brassicacoraphanus and its parents.Moreover,the miRNA expression profiles were characterized and 204 miRNAs with differential expression were obtained.Further analysis showed that 184 miRNAs were non-additively expressed in Brassicacoraphanus.At last,the potential regulatory network of flavonoid metabolism in Brassicacoraphanus was analyzed by multi-omics data,suggesting possible roles of miR858a and miR157a in regulating flavonoid synthesis pathway in Brassicacoraphanus.Taken together,this study provides useful resources for probing globalmiRNA expression patterns in Brassicacoraphanus,which facilitates regulatory mechanism research on the biosynthesis pathway of secondary metabolites in Brassicacoraphanus.
基金supported in part by the National Natural Science Foundation of China(Grant Nos.52175122 and 52075456)the Sichuan Science and Technology Program,China(Grant No.2023NSFSC0362)+1 种基金the Sichuan Province Innovative Talent Funding Project for Postdoctoral Fellows,China(Grant No.BX202214)the China Postdoctoral Science Foundation(Grant No.2023M732917).
文摘The failure types in gear systems vary,with typical ones mainly including pitting,cracking,wear,and broken teeth.Different modeling and stiffness calculation methods have been developed for various gear failure types.A unified method for typical gear failure modeling and stiffness calculation is introduced in this study by considering the deviations in the time-varying meshing stiffness(TVMS)of faulty gears resulting from the use of different methods.Specifically,a gear tooth is discretized into a large number of microelements expressed with a matrix,and unified models of typical gear failures are built by adjusting the values of the matrix microelements.The values and positions of the microelements in the tooth failure model matrix have the same physical meaning as the parameter variables in the potential energy method(PEM),so the matrix-based failure model can be perfectly matched with PEM.Afterward,a unified method for TVMS is established.Modeling of healthy and faulty gears with pitting,wear,crack,and broken tooth is performed with the matrix equation,and the corresponding TVMS values are calculated by incorporating the matrix models with PEM.On the basis of the results,the mechanism of typical fault types that affect TVMS is analyzed,and the conclusions are verified through the finite element method.The developed unified method is a promising technique for studying the dynamic response characteristics of gear systems with different failure types because of its superiority in eliminating stiffness deviations.
文摘运用网络药理学方法探究黄连解毒汤调节巨噬细胞炎症反应、糖酵解、鞘脂代谢和谷氨酰胺代谢等方面的多成分、多靶点、多通路的相互作用规律和调控网络,为创新药物研究奠定基础。通过TCMSP数据库筛选黄连解毒汤活性成分, PharmMapper数据库预测靶点蛋白, DAVID数据库进行通路注释和分析, Cytoscape 3.2.1软件构建"活性成分-靶点-通路"网络图, GENEMANIA数据库进行蛋白相互作用分析, Systems Dock Web Site数据库进行分子对接验证。预测结果表明,黄连解毒汤中共筛选出84个活性成分,作用靶点111个,其中与巨噬细胞炎症相关的靶点蛋白13个,涉及代谢通路14条;与糖酵解、鞘脂代谢、谷氨酰胺代谢相关的靶点蛋白34个,涉及代谢通路8条。炎症相关蛋白和代谢相关蛋白通过物理相关性、蛋白共表达等方式互相作用,小檗碱、黄芩苷和栀子苷与5个重要靶点均能较好结合。黄连解毒汤可能通过作用于糖酵解、鞘脂代谢和谷氨酰胺代谢的相关靶点,影响其代谢过程中的代谢产物和酶,从而调节巨噬细胞炎症反应。
