Results 71 to 80 of about 26,640,317 (249)
Shiyou jixie, 2014 基于水下卧式采油树使用工况和结构特点，确定了水下采油树静水压试验方案，完成了水下卧式采油树静水压试验装置设计和关键结构设计，在此基础上拓展了试验装置的功能和用途。该试验装置具备采油树静水压试验时所需的连接、密封、承载等功能，装置中螺纹式连接接头可用于金属密封垫环预紧力的测试，建立的金属密封垫环工作内压与预紧力之间的对应关系可用于研究海洋水下设备之间金属密封垫环的连接、挤压、变形和密封等问题，从而为现场使用提供参考依据。
doaj
Tau acetylation at K331 has limited impact on tau pathology in vivo
FEBS Letters, EarlyView.We mapped tau post‐translational modifications in humanized MAPT knock‐in mice and in amyloid‐bearing double knock‐in mice. Acetylation within the repeat domain, particularly around K331, showed modest increases under amyloid pathology. To test functional relevance, we generated MAPTK331Q knock‐in mice.
Shoko Hashimoto +3 more
wiley +1 more source
Shiyou jixie, 2014 国内连续管作业机虽然已经有了较大的发展，但是国内开发的相关软件功能模块比较单一，大部分连续管作业配套软件基本依靠国外公司开发的相关产品。介绍了4种国外连续管作业软件现状，并对其软件架构进行深入分析，认为一个完整的综合作业软件应该有几个应用模块：①数据采集模块。采集并监控作业关键参数，为力学模拟、流体模拟和疲劳评估提供基础数据。②力学模拟模块。对连续管管柱的力和应力进行综合模拟，并由此模拟作业过程中各种因素对作业的影响，可以进行作业前设计或实时监控作业过程。③流体模拟模块。对连续管及井筒内的流体进行模拟 ...
doaj
Calpain small subunit homodimerization is robust and calcium‐independent
FEBS Letters, EarlyView.Calpains dimerize via penta‐EF‐hand (PEF) domains. Using single‐molecule force spectroscopy, we measured the strength and kinetics of PEF–PEF homodimer binding. The interaction is robust, shows a transient conformational step before dissociation, and remains largely insensitive to Ca2+.
Nesha May O. Andoy +4 more
wiley +1 more source
Shiyou jixie, 2014 自动液压动力卡瓦是井口机械自动化的重要一环。介绍了液压动力卡瓦的产品分类及特点，概述了液压动力卡瓦技术发展现状，尤其对当前NOV、B+V以及Weatherford公司的典型液压动力卡瓦的结构参数和性能特点进行了重点分析研究。最后指出了液压动力卡瓦的发展趋势：①向承载多样化，夹持多元化方向发展；②向高安全性、高可靠性方向发展；③向控制操作智能化、集成化方向发展。
doaj
Structural insights into an engineered feruloyl esterase with improved MHET degrading properties
FEBS Letters, EarlyView.A feruloyl esterase was engineered to mimic key features of MHETase, enhancing the degradation of PET oligomers. Structural and computational analysis reveal how a point mutation stabilizes the active site and reshapes the binding cleft, expading substrate scope.
Panagiota Karampa +5 more
wiley +1 more source
Shiyou jixie, 2015 涡轮钻具轴承组在恶劣的工作环境中受到钻压、水力载荷以及钻进冲击与振动的作用，容易发生磨损现象，直接影响涡轮钻具的使用寿命。以φ127 mm涡轮钻具为例，根据弹塑性力学和赫兹接触理论，运用ABAQUS软件建立定子－滚珠－转子非线性接触问题有限元模型，针对不同磨损程度的滚珠轴承进行了数值模拟分析。研究结果表明，随磨损量的增大，轴承定子、转子与滚珠的接触面积逐渐减小，应力集中现象加剧，接触应力明显增大；最大接触应力出现在滚珠上，且与磨损量呈现非线性关系；相同工况下，磨损2 ...
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Gut microbiome and aging—A dynamic interplay of microbes, metabolites, and the immune system
FEBS Letters, EarlyView.Age‐dependent shifts in microbial communities engender shifts in microbial metabolite profiles. These in turn drive shifts in barrier surface permeability of the gut and brain and induce immune activation. When paired with preexisting age‐related chronic inflammation this increases the risk of neuroinflammation and neurodegenerative diseases.
Aaron Mehl, Eran Blacher
wiley +1 more source
Shiyou jixie, 2015 针对水平井作业机器人的结构特点，采用分布式结构理论，设计了基于PIC18F2620微控制器的1个上位机和多个分布式下位机的2层分布式控制系统。上位机通过电力线向下位机发送控制指令，控制相应的下位机控制模块完成特定的功能，同时实时接收下位机反馈的状态监测参数，并在人机交互界面上实时显示和判断水平井作业机器人的工作状态；上位机与下位机之间采用电力线载波通信技术实现电力传输和数据通信。通信试验和综合测试结果表明，水平井作业机器人分布式控制系统运行稳定，通信实时性强，满足水平井作业机器人的控制要求。
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FEBS Letters, EarlyView.Biomolecular condensates formed by fused in sarcoma (FUS) are dissolved by high ATP concentrations yet persist in cells. Using a reconstituted system, we demonstrate that valosin‐containing protein (VCP), an AAA+ ATPase, counteracts ATP‐driven dissolution of FUS condensates through its D2 ATPase activity.
Hitomi Kimura +2 more
wiley +1 more source