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Genetic lineage tracing identifies adaptive mechanisms of pancreatic islet β cells in various mouse models of diabetes with distinct age of initiation

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Science China(Life Sciences) 2024年第3期67卷 504-517页

作者： Qi Fu Yu Qian Hemin Jiang Yunqiang He Hao dai Yang Chen Zhiqing Xia Yucheng Liang Yuncai Zhou Rui Gao shuai Zheng Hui Lv Min Sun Kuanfeng Xu Tao Yang Department of Endocrinology the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China

During the pathogenesis of type 1 diabetes(T1D) and type 2 diabetes(T2D), pancreatic islets, especially the β cells, face significant challenges. These insulin-producing cells adopt a regeneration strategy to compensate for the shortage of insulin, but the exact mechanism needs to be defined. High-fat diet(HFD) and streptozotocin(STZ) treatment are well-established models to study islet damage in T2D and T1D respectively. Therefore, we applied these two diabetic mouse models, triggered at different ages, to pursue the cell fate transition of isletβ cells. Cre-LoxP systems were used to generate islet cell type-specific(α, β, or δ) green fluorescent protein(GFP)-labeled mice for genetic lineage tracing, thereinto β-cell GFP-labeled mice were tamoxifen induced. Single-cell RNA sequencing(scRNA-seq) was used to investigate the evolutionary trajectories and molecular mechanisms of the GFP-labeled β cells in STZ-treated mice. STZ-induced diabetes caused extensive dedifferentiation of β cells and some of which transdifferentiated into α or δ cells in both youth-and adulthood-initiated mice while this phenomenon was barely observed in HFD models. β cells in HFD mice were expanded via self-replication rather than via transdifferentiation from α or δ cells, in contrast, α or δ cells were induced to transdifferentiate into β cells in STZ-treated mice(both youthand adulthood-initiated). In addition to the re-dedifferentiation of β cells, it is also highly likely that these “α or δ” cells transdifferentiated from pre-existing β cells could also re-trans-differentiate into insulin-producing β cells and be beneficial to islet recovery. The analysis of ScRNA-seq revealed that several pathways including mitochondrial function, chromatin modification, and remodeling are crucial in the dynamic transition of β cells. Our findings shed light on how islet β cells overcome the deficit of insulin and the molecular mechanism of islet recovery in T1D and T2D pathogenesis.

关键词： islet regeneration lineage tracing high fat diet(HFD) streptozotocin(STZ)

基于最优解析树提取的多功能雷达状态快速估计方法

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电子学报 2016年第3期44卷 514-519页

作者：代鹂鹏王布宏曹帅沈海鸥空军工程大学信息与导航学院陕西西安710077

针对基于文法建模的多功能雷达(Multi-Function Radar,MFR)参数估计领域中常规算法具有的高运算复杂度问题,提出一种快速估计算法.该算法利用文法的派生过程仅与文法结构有关,而与文法概率参数无关这一事实,利用库克-杨-卡塞米(Cocke-Yo... 详细信息

针对基于文法建模的多功能雷达(Multi-Function Radar,MFR)参数估计领域中常规算法具有的高运算复杂度问题,提出一种快速估计算法.该算法利用文法的派生过程仅与文法结构有关,而与文法概率参数无关这一事实,利用库克-杨-卡塞米(Cocke-Younger-Kasami,CYK)算法对截获雷达数据序列进行预处理,构造出可以反映该序列派生过程的解析表,进而从该解析表中提取出序列的最优解析树,然后利用改进的Viterbi-Score算法对雷达文法概率参数进行快速估计.论文仿真分析了该算法的计算复杂度、存储复杂度和估计精度,实验结果表明了该算法相对于常规算法,可以减少60%左右的计算量.

关键词：多功能雷达随机上下文无关语法解析表解析树

Advances in Atmospheric Radiation:Theories,Models,and Their ***Ⅱ:Radiative Transfer Models and Related Applications

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Journal of Meteorological Research 2024年第2期38卷 183-208页

作者： Hua ZHANG Feng ZHANG Lei LIU Yuzhi LIU Husi LETU Yuanjian YANG Zhengqiang LI Kun WU shuai HU Ming LI Tie dai Fei WANG Zhili WANG Yuxiang LING Yining SHI Chao LIU State Key Laboratory of Severe Weather and Institute of Climate System Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044 Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438 College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073 College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000 State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101 School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing 100081

The subject of“atmospheric radiation”includes not only fundamental theories on atmospheric gaseous absorption and the scattering and radiative transfer of particles(molecules,cloud,and aerosols),but also their applications in weather,climate,and atmospheric remote sensing,and is an essential part of the atmospheric *** review includes two parts(Part I and PartⅡ);following the first part on gaseous absorption and particle scattering,this part(PartⅡ)reports the progress that has been made in radiative transfer theories,models,and their common applications,focusing particularly on the contributions from Chinese *** recent achievements on radiative transfer models and methods developed for weather and climate studies and for atmospheric remote sensing are firstly ***,the associated applications,such as surface radiation estimation,satellite remote sensing algorithms,radiative parameterization for climate models,and radiative-forcing related climate change studies are summarized,which further reveals the importance of radiative transfer theories and models.

关键词： atmospheric radiation radiative transfer remote sensing radiative forcing climate change

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城市与大都市货物运输交通:现有模型综述

交通运输系统工程与信息 2012年第4期12卷 106-114页

作者：周江评戴帅美国爱荷华州立大学爱荷华州艾姆斯市50011 公安部道路交通安全研究中心北京100062

货物运输模型的发展尚处于初级阶段,还未得到应有的重视.本文分析了各模型的基本过程、技术路线、优势及劣势,从现有文献中综合概括出全面统一的评价标准,并对不同模型性能进行评价.结果表明,相较其它模型,基于出行链的模型可更好地模... 详细信息

货物运输模型的发展尚处于初级阶段,还未得到应有的重视.本文分析了各模型的基本过程、技术路线、优势及劣势,从现有文献中综合概括出全面统一的评价标准,并对不同模型性能进行评价.结果表明,相较其它模型,基于出行链的模型可更好地模拟实际情况.然而,每种模型都仅在某些方面优于其它模型,没有最优的货物运输交通模型.研究人员应基于问题实质和范畴等指标,而不是仅仅出于粗略的性能评价和个人偏好.

关键词：公路运输建模绩效评价货物运输都市区域

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回采巷道复合顶板分类研究

煤炭技术 2016年第1期35卷 84-86页

作者：代进王帅王红红山东科技大学矿业与安全工程学院山东青岛266590

煤层顶板岩性复合及分层厚度变化大,稳定性差异显著。针对巷道层状复合顶板条件,通过地质调查、现场钻孔窥视仪测试、理论分析计算等方法,对变化的复合顶板问题进行了研究。按照夹矸厚度的大小,将顶板分为4类:稳定顶板、中等稳定顶板、... 详细信息

煤层顶板岩性复合及分层厚度变化大,稳定性差异显著。针对巷道层状复合顶板条件,通过地质调查、现场钻孔窥视仪测试、理论分析计算等方法,对变化的复合顶板问题进行了研究。按照夹矸厚度的大小,将顶板分为4类:稳定顶板、中等稳定顶板、不稳定顶板及极不稳定顶板。

关键词：复合顶板顶板钢化软弱夹层

Improving the performance of crystalline Si solar cell by high-pressure hydrogenation

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Chinese Physics B 2020年第11期29卷 548-552页

作者： Xi-Yuan dai Yu-Chen Zhang Liang-Xin Wang Fei Hu Zhi-Yuan Yu shuai Li Shu-Jie Li Xin-Ju Yang Ming Lu Department of Optical Science and Engineering and Shanghai Ultra-Precision Optical Manufacturing Engineering Center Fudan UniversityShanghai 200433China School of Microelectronics Fudan UniversityShanghai 200433China Department of Physics Fudan UniversityShanghai 200433China

We report an approach of high-pressure hydrogenation to improve the performance of crystalline Si(c-Si) solar ***-received p-type c-Si wafer-based PN junctions were subjected to high-pressure(2.5 MPa) hydrogen atmosphere at 200 ℃,followed by evaporating antireflection layers,passivation layers,and front and rear *** efficiency of the so prepared c-Si solar cell was found to increase evidently after high-pressure hydrogenation,with a maximal enhancement of 10%.The incorporation of hydrogen by Si solar cells was identified,and hydrogen passivation of dangling bonds in Si was *** to the regular approach of hydrogen plasma passivation,the approach of high-pressure hydrogenation reported here needs no post-hydrogenation treatment,and can be more convenient and efficient to use in improving the performances of the c-Si and other solar cells.

关键词： high-pressure hydrogenation Si solar cell bulk passivation

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光束质量对平顶衍射光学元件输出的影响

光学学报 2023年第14期43卷 40-48页

作者：戴深宇郑昕赵帅季华实验室光电科学与技术研究部广东佛山528200

衍射光学元件(DOE)对入射光束的波长、束宽、光束质量等参数都有很高的要求,其中光束质量的影响无法直接通过相干光场的衍射积分得出。本文利用高斯谢尔模型(GSM)光束分析了光束质量对平顶衍射光学元件输出的影响。采用对称迭代傅里叶... 详细信息

衍射光学元件(DOE)对入射光束的波长、束宽、光束质量等参数都有很高的要求,其中光束质量的影响无法直接通过相干光场的衍射积分得出。本文利用高斯谢尔模型(GSM)光束分析了光束质量对平顶衍射光学元件输出的影响。采用对称迭代傅里叶变换算法设计了输出平顶光斑的DOE。用模式分解的方法研究了不同光束质量的光束经该DOE后的输出光斑,发现光束质量因子增加会使输出光斑平顶区尺寸减小,导致DOE失效。从交叉谱密度出发,表明DOE的输出光斑是相干部分和非相干部分的卷积,其中非相干部分是导致输出光斑劣化的原因。给出了平顶衍射光学元件适用的最大M^(2)因子与输入和输出光束尺寸之间的关系。给出了一种GSM光束整形DOE的设计方法,该方法有助于在低光束质量激光器中实现DOE的应用。

关键词：衍射与光栅衍射光学元件光束质量高斯谢尔模型模式分解

面向控制规律设计的民用航空发动机建模方法研究

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机械工程学报 2024年第16期60卷 222-230页

作者：刘帅王伟白杰戴士杰中国民航大学民航航空器适航审定技术重点实验室天津300300 中国民航大学安全科学与工程学院天津300300 河北工业大学机械工程学院天津300130

通过部件法建立的民用航空发动机非线性气动热力模型具有结构复杂、参数强耦合的特点,难以直接用于控制规律设计。针对民用航空发动机控制规律设计难度大、工作量繁重且只能用于标称点线性化模型的问题,提出一种面向控制规律设计的民用... 详细信息

通过部件法建立的民用航空发动机非线性气动热力模型具有结构复杂、参数强耦合的特点,难以直接用于控制规律设计。针对民用航空发动机控制规律设计难度大、工作量繁重且只能用于标称点线性化模型的问题,提出一种面向控制规律设计的民用航空发动机建模方法。根据航空发动机控制功能进行结构简化,利用转子动力学建模和燃烧反应动力学建模建立微分形式的航空发动机控制标准型模型。该模型建立了航空发动机全包线内控制所需参数的对应关系,非线性控制方法能够直接用于航空发动机控制规律设计,在一定程度上简化控制规律设计的工作量与难度。以DGEN380型航空发动机为例建立控制标准型模型,通过试验验证模型精度,且给出控制规律设计实例。面向控制规律设计的民用航空发动机建模方法达到了预期目标。

关键词：航空发动机建模控制标准型模型控制规律

Analysis of raft foundation design based on considering influence of superstructure stiffness

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Global Geology 2009年第1期12卷 28-31页

作者： WANG Bin QIU Jianhui ZHAO Dong YANG Xi dai shuai College of Construction Engineering Jilin University Changchun 130026 China Design Institute of Jilin Architectural and Civil Engineering Institute Changchun 130021 China

The finite element method was used for analysis of raft foundation design in high-rise *** with other conventional methods,this method is more adapted to the practical condition since both superstructure stiffness and soil conditions were considered in *** calculation results by example show that the base reaction is more uniform and the maximum reaction decreases ***,the raft foundation design is more economic without any loss of security for high-rise building.

关键词： superstructure stiffness soil raft finite element method interaction