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deCS:A Tool for Systematic Cell Type Annotations of Single-cell RNA Sequencing Data among Human Tissues

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Genomics, Proteomics & Bioinformatics 2023年第2期21卷 370-384页

作者： Guangsheng Pei Fangfang Yan Lukas m.Simon yulin Dai Peilin Jia Zhongming Zhao Center for Precision Health School of Biomedical InformaticsThe University of Texas Health Science Center at HoustonHoustonTX 77030USA Therapeutic Innovation Center Baylor College of MedicineHoustonTX 77030USA Human Genetics Center School of Public HealthThe University of Texas Health Science Center at HoustonHoustonTX 77030USA mD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences HoustonTX 77030USA Department of Biomedical Informatics Vanderbilt University Medical CenterNashvilleTN 37203USA CAS Key Laboratory of Genomic and Precision medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China

Single-cell RNA sequencing(scRNA-seq)is revolutionizing the study of complex and dynamic cellular ***,cell type annotation remains a main challenge as it largely relies on a priori knowledge and manual curation,which is cumbersome and *** increasing number of scRNA-seq datasets,as well as numerous published genetic studies,has motivated us to build a comprehensive human cell type reference ***,we present decoding Cell type Specificity(deCS),an automatic cell type annotation method augmented by a comprehensive collection of human cell type expression profiles and marker *** used deCS to annotate scRNAseq data from various tissue types and systematically evaluated the annotation accuracy under different conditions,including reference panels,sequencing depth,and feature selection *** results demonstrate that expanding the references is critical for improving annotation *** to many existing state-of-the-art annotation tools,deCS significantly reduced computation time and increased *** can be integrated into the standard scRNA-seq analytical pipeline to enhance cell type ***,we demonstrated the broad utility of deCS to identify trait-cell type associations in 51 human complex traits,providing deep insights into the cellular mechanisms underlying disease pathogenesis.

关键词： Cell type-specific enrichment analysis scRNA-seq Cell type annotation Trait-cell type association Cell typemarkergene

IAA-Net:一种实孔径扫描雷达迭代自适应角超分辨成像方法

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雷达学报（中英文） 2024年第5期13卷 1073-1091页

作者：毛德庆杨建宇杨明杰张永超张寅黄钰林电子科技大学信息与通信工程学院成都611731

实孔径雷达(RAR)通过天线扫描工作,以获取大范围探测区域内目标的观测信息。但是,由于雷达天线尺寸小,受天线衍射机理限制,与距离分辨率相比,其角分辨率通常较低。角超分辨处理方法,可利用天线方向图与目标散射间的卷积关系,通过求解卷... 详细信息

实孔径雷达(RAR)通过天线扫描工作,以获取大范围探测区域内目标的观测信息。但是,由于雷达天线尺寸小,受天线衍射机理限制,与距离分辨率相比,其角分辨率通常较低。角超分辨处理方法,可利用天线方向图与目标散射间的卷积关系,通过求解卷积反演问题,以提高扫描雷达角分辨率。但是,由于测量矩阵的低秩特性,传统角超分辨处理方法,存在正则化参数选择难、迭代更新慢等问题,并且在低信噪比条件下,角超分辨处理性能明显下降。针对上述问题,该文提出了一种基于深度网络的迭代自适应实孔径扫描雷达角超分辨成像方法。首先,该文将实孔径扫描雷达的卷积反演问题转化为回波自相关矩阵反演求解问题,以改善求逆矩阵的病态性;其次,将可学习的修正矩阵引入到迭代自适应求解方法中,以实现迭代自适应求解方法与深度网络的结合;最后,通过迭代学习更新回波自相关矩阵,降低噪声对反演结果的影响,提高实孔径雷达的角分辨率。仿真及实测数据结果表明,所提方法可避免传统算法中的手动参数选择和迭代更新慢等问题。同时,由于深度网络的学习拟合能力,所提方法可在低信噪比条件下保持良好的角超分辨性能。

关键词：实孔径雷达角超分辨重建深度网络迭代自适应参数选择

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Compressed Sensing of Wireless Sensor Networks Data with missed measurements

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Chinese Journal of Electronics 2015年第2期24卷 388-392页

作者： WANG Kai LIU yulin WAN Qun JING Xiaojun Chongqing Communication Institute China Electronic System Engineering Company University of Electronic Science and Technology of China Beijing University of Posts and Telecommunications

In Wireless sensor networks(WSNs),missed measurements may be caused by the sensor malfunction and interruption of communication between sensor nodes. The feasibility of exact recovery of WSNs data with missed measurements is analyzed in the framework of compressed sensing. A new incomplete measurement model was developed and the data reconstruction algorithm was proposed. The required number of the missing measurements and the sparsity condition of network data are found for exact compressed sensing of WSNs *** derivation shows that a WSNs data of length N with no more than m/(log(N/m) + 1) nonzero coefficients can be exactly recovered with m Gaussian measurements,provided that fraction of the missed measurements is less than a quarter of the Restricted isometry property(RIP)constant squared. Simulation results validate the theoretical results.

关键词： Wireless sensor networks Compressed sensing missed measurements Data reconstruction

An Al–Al interpenetrating-phase com.osite by 3D printing and hot extrusion

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International Journal of minerals,metallurgy and materials 2023年第4期30卷 678-688页

作者： yulin Lin Di Wang Chao Yang Weiwen Zhang Zhi Wang School of mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China Guangdong Key Laboratory for Processing and Forming of Advanced metallic materials South China University of TechnologyGuangzhou 510640China

We report a process route to fabricate an Al–Al interpenetrating-phase com.osite by combining the Al–mg–mn–Sc–Zr lattice structure and Al_(84)Ni_(7)Gd_(6)Co_(3)nanostructured structure. The lattice structure was produced by the selective laser melting and subsequently filled with the Al_(84)Ni_(7)Gd_(6)Co_(3)amorphous powder, and finally the mixture was used for hot extrusion to produce bulk samples. The results show that the com.osites achieve a high densification and good interface bonding due to the element diffusion and plastic deformation during hot *** bulk samples show a heterogeneous structure with a combination of honeycomb lattice structure with an average grain size of less than1 μm and nanostructured area with a high volume fraction of nanometric intermetallics and nanograin α-Al. The heterogeneous structure leads to a bimodal mechanical zone with hard area and soft area giving rise to high strength and acceptable plasticity, where the compressive yield strength and the compressive plasticity can reach ~745 mPa and ~30%, respectively. The high strength can be explained by the rule of mixture,the grain boundary strengthening, and the back stress, while the acceptable plasticity is mainly owing to the confinement effect of the nanostructured area retarding the brittle fracture behavior.

关键词： Al-based com.osites heterogeneous structure additive manufacturing mechanical properties

边墩沉降致连续简支桥段纵连线桥系统层间联结劣化规律

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防灾减灾工程学报 2024年第3期44卷 623-631页

作者：冯玉林何帅蒋丽忠周旺保颜建伟华东交通大学土木建筑学院江西南昌330013 华东交通大学轨道交通基础设施性能监测与保障国家重点实验室江西南昌330013 中南大学高速铁路建造技术国家工程研究中心湖南长沙410075

为研究边墩沉降致纵连板式无砟轨道-连续梁桥系统(纵连线桥系统)层间联结劣化状态,在考虑边墩沉降与层间接触不连续影响的基础上,建立纵连线桥系统非线性空间模型,采用前期提出的理论模型对其进行验证,据此分析边墩沉降下纵连线桥系统... 详细信息

为研究边墩沉降致纵连板式无砟轨道-连续梁桥系统(纵连线桥系统)层间联结劣化状态,在考虑边墩沉降与层间接触不连续影响的基础上,建立纵连线桥系统非线性空间模型,采用前期提出的理论模型对其进行验证,据此分析边墩沉降下纵连线桥系统典型变形模式,层间联结失效的演化过程、发展规律及出现位置等。结果表明:建立的空间模型准确可靠;边墩沉降下,线桥系统会产生跟随变形、自重变形和悬停分离三种变形模式;沉降墩、与沉降墩临近的简支梁墩及连续梁桥另一侧边墩上方会出现层间联结失效,与沉降墩临近的简支梁墩、连续梁桥全部桥墩上的支座均会发生破坏;边墩沉降处板底脱空高度可用边墩沉降值减去连续梁桥变形限值进行描述;各脱空区长度均随边墩沉降幅值增加而增大,与沉降墩临近的简支梁墩左、右两侧区域脱空长度成正对称分布,连续梁另一边墩处脱空长度值只与连续梁变形有关,始终维持在2.56 m。

关键词：高速铁路桥墩沉降损伤演化悬停分离连续梁桥

小鼠丘脑背内侧核内VGLUT2阳性神经元传入联系的形态学研究

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神经解剖学杂志 2024年第3期40卷 287-294页

作者：冯慧洁彭霏薛美琪阮彩莲董玉琳空军军医大学基础医学院人体解剖与组织胚胎学教研室暨梁銶琚脑研究中心西安710032 延安大学基础医学院人体解剖学教研室延安716000 空军军医大学基础医学院学员五大队西安710032

目的:利用狂犬病病毒(RV)介导的逆行跨单级突触追踪技术,观察丘脑背内侧核(mD)内囊泡膜谷氨酸转运体2(VGLUT2)阳性神经元的全脑突触前神经元分布。方法:将RV的辅助病毒注射至VGLUT2-ires-Cre转基因小鼠右侧mD,两周后将RV注入相同区域。... 详细信息

目的:利用狂犬病病毒(RV)介导的逆行跨单级突触追踪技术,观察丘脑背内侧核(mD)内囊泡膜谷氨酸转运体2(VGLUT2)阳性神经元的全脑突触前神经元分布。方法:将RV的辅助病毒注射至VGLUT2-ires-Cre转基因小鼠右侧mD,两周后将RV注入相同区域。一周后灌注取材,进行全脑扫描,观察RV标记的突触前神经元在全脑的分布。结果:将RV病毒注入VGLUT2-ires-Cre小鼠mD后,在皮质和脑干内可观察到密集的突触前神经元。皮质内逆标神经元多分布于运动皮质、内侧前额叶皮质、眶额皮质和岛叶;丘脑内多见于丘脑网状核和下丘脑外侧区等;而脑干逆标神经元则主要分布在臂旁外侧核、中脑导水管周围灰质和中缝核等部位。结论:mD内VGLUT2阳性神经元一方面可接受来自脑干的上行纤维的投射,或丘脑网状核的信息调控;另一方面作为高阶丘脑也可接受皮质的下行投射,参与脑内的多种功能。以上结果为研究mD的功能及相关神经环路的机制提供了形态学基础。

关键词：丘脑背内侧核狂犬病病毒囊泡膜谷氨酸转运体2 小鼠

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大跨铁路斜拉桥下横梁自承式施工参数分析

铁道标准设计 2024年第1期68卷 102-107,125页

作者：李涛黄媛媛覃早占玉林邵俊虎中国铁路成都局集团有限公司成都610082 西南交通大学土木工程学院成都610031 中铁二局第五工程有限公司成都610091 成都大学建筑与土木工程学院成都610106

横梁自承式施工方法由于可节省施工支架造价,得到了广泛应用。为确定自承式施工中分层浇筑高度以及支架刚度合理取值,以明月峡长江大桥横梁施工为工程背景,采用midas/Civil有限元软件建立全桥施工阶段模型,对横梁分层浇筑高度和支架刚... 详细信息

横梁自承式施工方法由于可节省施工支架造价,得到了广泛应用。为确定自承式施工中分层浇筑高度以及支架刚度合理取值,以明月峡长江大桥横梁施工为工程背景,采用midas/Civil有限元软件建立全桥施工阶段模型,对横梁分层浇筑高度和支架刚度进行参数研究,分析上述参数对横梁应力和变形的影响规律。研究结果表明:第一层浇筑高度为1 m和2 m时,将会出现拉应力,不满足规范规定的要求;浇筑高度由3 m增至5 m时,在施工过程中横梁均受压且满足规范限值。随着分层高度增大,在横梁施工阶段,横梁上缘最小压应力最大可减小约1.5 mPa;横梁下缘最小压应力最多增大约1.3 mPa;在成桥阶段,横梁下缘最大压应力增大约0.5 mPa,上缘最小压应力减小约2 mPa。为使得横梁在运营阶段有足够的应力储备,建议第一层浇筑高度选为3 m。支架刚度由1×107 kN/m变化至2×10^(5) kN/m,横梁的应力和挠度基本不变;当支架刚度由2×10^(5) kN/m减小至1×10^(5) kN/m时,横梁上缘最小压应力减小约0.3 mPa,下缘最小压应力减小约0.4 mPa,挠度增加约1 mm,建议支架刚度宜大于2×10^(5) kN/m。

关键词：铁路桥大跨度斜拉桥下横梁自承式施工参数分析

黔西上二叠统煤系关键金属富集层时空分布及地质控制因素

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地质学报 2024年第8期98卷 2365-2378页

作者：杨天洋沈玉林金军黄文张云飞曾丽君姜帆赵雅中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221116 中国矿业大学资源与地球科学学院江苏徐州221008 贵州省煤层气页岩气工程技术研究中心贵州贵阳550081 贵州省煤田地质局贵州贵阳550025

黔西晚二叠世煤系关键金属元素富集层在垂向上叠置分布,但其在地层中的时空分布规律尚不清楚。详细研究关键金属富集层的时空分布规律可以预测其分布特征及了解该时期富集成矿规律与地质事件的联系。本文分析了煤系关键金属富集层的地... 详细信息

黔西晚二叠世煤系关键金属元素富集层在垂向上叠置分布,但其在地层中的时空分布规律尚不清楚。详细研究关键金属富集层的时空分布规律可以预测其分布特征及了解该时期富集成矿规律与地质事件的联系。本文分析了煤系关键金属富集层的地球化学特征及垂向分布规律,探讨了其形成的地质控制因素。结果表明煤系Ga-Zr-Nb-REY关键金属富集层为自然伽马高异常岩层,具有低Sr/Ba、较高的Rb/Sr和CIAcorr值,以及相对较高的V/Ni和V/(V+Ni),表明在气候相对炎热、海平面仍相对较低时期形成于水体相对较深的缺氧环境中。根据富集层垂向分布特征总结了6种Ga-Zr-Nb-REY富集层沉积序列及3种Li富集层沉积序列,其中Ga-Zr-Nb-REY富集层垂向分布特征表明富集层在沉积旋回内处于相对一致的层位。m2井长兴组的Li富集层在垂向上有显著的旋回性。Ga-Zr-Nb-REY关键金属富集层为含板内火山灰层,其垂向叠置规律及关键金属元素含量受板内火山活动规律及强度控制。古地理格局控制了沉积物在地表遭受淋滤作用的强度,经历较弱或未经历淋滤作用的含板内火山灰层具有关键金属元素富集的特征。弱水动力条件利于火山灰的保存,局限环境可能是形成Li富集层的重要原因。在热液流体的影响下形成了黔西地区偶现的Li、Ti富集层。这种富集成矿规律及分布模式可以有效地预测关键金属元素富集层位的时空分布规律。

关键词：关键金属时空分布规律地质控因晚二叠世

A new nonlinear force model to replace the Hertzian contact model in a rigid-rotor ball bearing system

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Applied mathematics and mechanics(English Edition) 2018年第3期39卷 365-378页

作者： yulin JIN Zhenyong LU Rui YANG Lei HoU Yushu CHEN School of Astronautics Harbin Institute of Technology School of Energy Science and Engineering Harbin Institute of Technology

A new nonlinear force model based on experimental data is proposed to replace the classical Hertzian contact model to solve the fractional index nonlinearity in a ball bearing system. Firstly, the radial force and the radial deformation are measured by statics experiments, and the data are fitted respectively by using the Hertzian contact model and the cubic polynomial model. Then~ the two models are compared with the approximation formula appearing in Aeroengine Design manual. In consequence, the two models are equivalent in an allowable deformation range. After that, the relationship of contact force and contact deformation for single rolling element between the races is cal- culated based on statics equilibrium to obtain the two kinds of nonlinear dynamic models in a rigid-rotor ball bearing system. Finally~ the displacement response and frequency spectrum for the two system models are compared quantitatively at different rotational speeds, and then the structures of frequency-amplitude curves over a wide speed range are compared qualitatively under different levels of radial clearance, amplitude of excitation, and mass of supporting rotor. The results demonstrate that the cubic polynomial model can take place of the Hertzian contact model in a range of deformation.

关键词： rolling element bearing, Hertzian contact, fractional index cubic polyno-miali rotor ball bearing system