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Description and Phylogenetic Position of Dinosaur Eggshells from the Luanchuan Area of Western Henan Province,China

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Acta Geologica Sinica(English Edition) 2011年第1期85卷 66-74页

作者： Kohei TANAKA LU Junchang Yoshitsugu KOBAYASHI Darla K. ZELENITSKY XU li JIA songhai QIN Shuang TANG Min＇ an Department of Geoscience University of Calgary Calgary T2N 1N4 Canada Institute of Geology Chinese Academy of Geological Sciences Beijing 10037 China Hokkaido University Museum Hokkaido University Sapporo 060-0810 Japan Henan Geological Museum Zhengzhou 450016 China North China University of Water Conservancy and Electric Power Zhengzhou 450011 China

Here, we examine 145 dinosaur eggshells from a new fossil locality in the Qiupa Formation （Upper Cretaceous） of the Luanchuan area in western Henan Province, China. The eggshells display elongatoolithid macro- and microstructures, including ridges and nodes on the outer surface, two ultrastructurai layers, and an undulatory boundary between the mammillary and continuous layers. A phylogenic analysis shows that the Luanchuan eggshells belong to the ooclade Elongatoolithidae. Within Elongatoolithidae, the thickness ratio of the mammillary layer to the entire eggshell, and the porosity of the Luanchuan eggshells are comparable to the oogenera Macroolithus and Elongatoolithus. There is no direct evidence for the taxonomic identity of the Luanchuan eggshells; however, they were likely laid by oviraptorids based on their phylogenetic position and their similarities with known oviraptorid eggs.

关键词： dinosaur eggshells Qiupa Formation Late Cretaceous Luanchuan Henan Province,China

不同林龄桉树人工林土壤碳氮磷钾化学计量特征

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桉树科技 2023年第2期40卷 53-58页

作者：陆艳武易弘韬石驭天申礼凤黄雪清李松海广西国有高峰林场广西南宁530002

为研究桂中地区不同林龄桉树人工林土壤有机碳、全氮、全磷、全钾差异及化学计量比特征,以5个林龄桉树人工林土壤为研究对象,对相关指标进行分析。结果表明:不同土层的土壤有机碳、全氮、全磷、全钾及化学计量比特征虽有差异,但与林龄... 详细信息

为研究桂中地区不同林龄桉树人工林土壤有机碳、全氮、全磷、全钾差异及化学计量比特征,以5个林龄桉树人工林土壤为研究对象,对相关指标进行分析。结果表明:不同土层的土壤有机碳、全氮、全磷、全钾及化学计量比特征虽有差异,但与林龄未表现出明显的变化规律。C∶K、N∶K、P∶K在3年生人工林土壤中达到最大值。土壤有机碳与全氮、全磷、全钾呈极显著正相关。全氮与全磷呈极显著正相关,与C∶N呈极显著负相关。全磷与P∶K呈极显著正相关,与C∶P呈极显著负相关。全钾与C∶K、N∶K、P∶K呈极显著负相关。在本地区的桉树营林过程中,需加强有机碳和磷肥的养分管理。

关键词：生态化学计量土壤养分桉树人工林

Genome-Wide Identification of Tomato (Solanum lycopersicum L.) CKX Gene Family and Expression Analysis in the Callus Tissue under Zeatin Treatment

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1143-1158页

作者： Zhengfeng Lai Dongmei lian Shaoping Zhang Yudong Ju Bizhen lin Yunfa Yao songhai Wu Jianji Hong Zhou li Subtropical Agriculture Research Institute Fujian Academy of Agricultural SciencesZhangzhou363005China

The cytokinin oxidase/dehydrogenase(CKX)enzyme is essential for controlling theﬂuctuating levels of endogen-ous cytokinin(CK)and has a signiﬁcant impact on different aspects of plant growth and ***-less,there is limited knowledge about CKX genes in tomato(Solanum lycopersicum L.).Here we performed genome-wide identiﬁcation and analysis of nine SlCKX family members in tomatoes using bioinformatics *** results revealed that nine SlCKX genes were unevenly distributed onﬁve chromosomes(Chr.1,Chr.4,Chr.8,Chr.10,and Chr.12).The amino acid length,isoelectric points,and molecular weight of the nine SlCKX proteins ranged from 453 to 553,5.77 to 8.59,and 51.661 to 62.494 kD,*** localization analysis indi-cated that SlCKX2 proteins were located in both the vacuole and cytoplasmic matrix;SlCKX3 and SlCKX5 pro-teins were located in the vacuole;and SlCKX1,4,6,7,8,and 9 proteins were located in the cytoplasmic ***,we observed differences in the gene structures and phylogenetic relationships of SlCKX proteins among different ***1-9 were positioned on two out of the three branches of the CKX phylogenetic tree in the multispecies phylogenetic tree construction,revealing their strong conservation within phylogenetic *** patterns of expression of CKX genes were noticed in callus cultures exposed to varying con-centrations of exogenous ZT,suggesting their roles in speciﬁc developmental and physiological functions in the regeneration *** results may facilitate subsequent functional analysis of SlCKX genes and provide valu-able insights for establishing an efﬁcient regeneration system for tomatoes.

关键词： Tomato SlCKX gene family phylogenetic relationships trans-zeatin expression pattern

Fast portrait automatic segmentation with coarse-to-fine CNNs

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Computer Aided Drafting,Design and Manufacturing 2017年第2期27卷 39-49页

作者： Zhang Xijin li Ruilong Zhang songhai Department of Computer Science and Technology Tsinghua University

In this paper, we propose a coarse-to-fine convolutional network framework designed with problem specific knowledge for fast automatic portrait segmentation. We built up a dataset of 7 100 portrait images which are frames from personal live show videos. The proposed network includes a coarse network which can learn global information and a fine network which utilizes local information to refine the coarse output. Additionally, an auxiliary contour loss is introduced to help training the coarse network. The proposed framework shows higher accuracy than the widely-used fully convolutional network. With light-weight post-processing, the predicted foreground mask can be used in real-time portrait video editing tasks such as background replacement.

关键词： convolutional neural network image segmentation machine learning

Characterization of a novel mouse model with genetic deletion of CD177

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Protein & Cell 2015年第2期6卷 117-126页

作者： Qing Xie Julia Klesney-Tait Kathy Keck Corey Parlet Nicholas Borcherding Ryan Kolb Wei li Lorraine Tygrett Thomas Waldschmidt Alicia Olivier songhai Chen Guang-Hui liu Guang-Hui liu Xiangrui li Weizhou Zhang College of Veterinary Medicine Nanjing Agricultural University Nanjing 210095 China Department of Pathology Holden Comprehensive Cancer Center Carver College of Medicine/University of Iowa Iowa IA 52242 USA Department of Internal Medicine Carver College of Medicine/University of Iowa Iowa IA 52242 USA Department of Pharmacology Carver College of Medicine/University of Iowa Iowa IA 52242 USA National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Beijing Institute for Brain Disorders Beijing 100069 China

Neutrophils play an essential role in the innate immune response to infection. Neutrophils migrate from the vasculature into the tissue in response to infection. Recently, a neutrophil cell surface receptor, CD177, was shown to help mediate neutrophil migration across the endothelium through interactions with PECAMI. We examined a publicly available gene array dataset of CD177 expression from human neutrophils following pulmonary endotoxin instillation. Among all 22,214 genes examined, CD177 mRNA was the most upregu- lated following endotoxin exposure. The high level of CD177 expression is also maintained in airspace neu- trophils, suggesting a potential involvement of CD177 in neutrophil infiltration under infectious diseases. To determine the role of CD177 in neutrophils in vivo, we constructed a CD177-genetic knockout mouse model. The mice with homozygous deletion of CD177 have no discernible phenotype and no significant change in immune cells, other than decreased neutrophil counts in peripheral blood. We examined the role of CD177 in neutrophil accumulation using a skin infection model with Staphylococcus aureus. CD177 deletion reducedneutrophil counts in inflammatory skin caused by S. aureus. Mechanistically we found that CD177 deletion in mouse neutrophils has no significant impact in CXCli/ KC- or fMLP-induced migration, but led to significant cell death. Herein we established a novel genetic mouse model to study the role of CD177 and found that CD177 plays an important role in neutrophils.

关键词： CD177 neutrophil mouse model geneticdeletion

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基于兴趣点的北京市住宅生活便利度指数研究

计算机辅助设计与图形学学报 2021年第4期33卷 609-615页

作者：李健张松海清华大学计算机科学与技术系北京100084

住宅的生活便利度指数指住宅居民在一定范围内可利用的设施种类与数量,是城市宜居度的重要指标.兴趣点(point of interest, POI)数据是一组包含物理实体属性的地理坐标点,具有数据种类详尽、粒度精细、范围广和时效性强的优点.基于高德... 详细信息

住宅的生活便利度指数指住宅居民在一定范围内可利用的设施种类与数量,是城市宜居度的重要指标.兴趣点(point of interest, POI)数据是一组包含物理实体属性的地理坐标点,具有数据种类详尽、粒度精细、范围广和时效性强的优点.基于高德POI数据,对北京市城区住宅的生活便利度指数进行研究,提出面向地铁出行的各向异性距离度量方法,根据构建的生活便利度指数指标体系将住宅分为优质、良好、中等和待改进4个等级.各等级住宅在城区中的空间分布结果表明,考虑地铁出行后,对住宅的生活便利度指数度量更为合理.

关键词：兴趣点数据生活便利度指数各向异性距离度量

沉浸式环境中多场景视觉提示信息可视化方法综述

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中国图象图形学报 2024年第1期29卷 1-21页

作者：任洋甫李志强张松海青海大学计算机技术与应用系西宁810016 清华大学计算机科学与技术系北京100084 国防大学联合作战学院北京100091

沉浸式环境是通过虚拟现实(virtual reality,VR)等技术为用户呈现趋近于真实的环境体验。虚拟现实是通过计算机生成现实世界的模拟环境,可以为用户提供丰富的沉浸感、交互性和想象力体验。用户在虚拟现实场景中,通过视觉可以快速熟悉环... 详细信息

沉浸式环境是通过虚拟现实(virtual reality,VR)等技术为用户呈现趋近于真实的环境体验。虚拟现实是通过计算机生成现实世界的模拟环境,可以为用户提供丰富的沉浸感、交互性和想象力体验。用户在虚拟现实场景中,通过视觉可以快速熟悉环境,获取场景内外的信息,还可以通过视觉完成与场景的交互,增强用户的感知。增强现实(augmented reality,AR)会将虚拟信息放置在真实场景中,用户可以与真实场景中的虚拟信息进行交互。为了充分了解视觉提示信息在虚拟现实等不同沉浸式场景中的研究,探究视觉信息提示方法的本源,本文按照信息提示位置的不同、功能和应用的不同进行区分,首先综述近年来在普通二维场景中的方法,通过技术对比和改进深入讨论了在三维虚拟现实或增强现实环境下对视觉提示信息可视化方法的研究。分析在虚拟现实或增强现实环境下与普通二维场景中显示的异同,同时展开视觉提示信息在多场景下对用户注意力等使用功能方面的研究介绍,以及全景视频观看等实际场景中的应用研究说明。本文通过对二维和三维场景视野外、场景中标签布局和注意力引导,以及全景视频观看等实际应用中的讨论,可以更详细地展示视觉提示信息在沉浸式环境和多场景中的研究前景与发展方向。

关键词：沉浸式环境虚拟现实(VR) 增强现实(AR) 多场景视觉提示信息全景视频注意力引导

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一种基于四叉树结构的动态多分辨率地形模型

计算机工程与应用 2006年第7期42卷 202-204页

作者：李偈张松海刘强清华大学软件学院北京100084

结合油田可视化项目,文章根据三维地形可视化中利用四叉树存储DEM数据的方法,提出了一种与视点相关的动态多分辨率地理模型的构造算法,主要讨论了该模型的多分辨率地形表示机制以及动态地形简化方法和评价函数等问题,试验结果表明,文中... 详细信息

结合油田可视化项目,文章根据三维地形可视化中利用四叉树存储DEM数据的方法,提出了一种与视点相关的动态多分辨率地理模型的构造算法,主要讨论了该模型的多分辨率地形表示机制以及动态地形简化方法和评价函数等问题,试验结果表明,文中的算法达到了预期目的,能应用于地形场景的三维可视化和漫游。

关键词：四叉树层次细节模型地形模型动态多分辨率

考虑流层间粘力的直流接地极线路招弧角间电弧运动模型研究

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高压电器 2021年第6期57卷 24-31,40页

作者：王涛郑连清范松海官瑞杨李昂重庆大学输配电装备及系统安全与新技术国家重点实验室重庆400044 国网四川省电力公司电力科学研究院成都610041 清华大学电机系电力系统及发电设备控制和仿真国家重点实验室北京100084 国网河南省电力公司检修公司郑州450004

直流接地极线路耐雷水平低,在遭受雷击和操作过电压时容易在绝缘子串上建立电弧,一般采取在绝缘子两端安装招弧角的方法来防止直流电弧烧蚀绝缘子。目前缺少招弧角的熄弧机理及电弧运动过程的研究,招弧角的安装均依据运行经验,缺少理论... 详细信息

直流接地极线路耐雷水平低,在遭受雷击和操作过电压时容易在绝缘子串上建立电弧,一般采取在绝缘子两端安装招弧角的方法来防止直流电弧烧蚀绝缘子。目前缺少招弧角的熄弧机理及电弧运动过程的研究,招弧角的安装均依据运行经验,缺少理论依据。文中采用链式电弧模型,考虑电流元间粘力的作用,建立了招弧角间直流电弧运动模型,提出了一种基于大矩阵存放电流元位置坐标的算法,在MATLAB中编制程序,仿真分析电弧运动过程及电弧受力,得出磁场力和热浮力为熄弧的主要动力的结论,为招弧角的安装提供理论依据。最后在小尺度直流电弧实验平台进行熄弧实验,验证了文中所建模型的有效性。

关键词：接地极线路招弧角粘力直流电弧运动模型