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O-GlcNAc修饰在糖尿病心肌病中的作用及机制研究进展
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作者 张静 常盼 +2 位作者 刘茹 蒋玲 王红 《成都医学院学报》 CAS 2024年第3期543-546,551,共5页
糖尿病是一种慢性代谢性紊乱疾病。据统计,我国2021年糖尿病患者数量已高达1.41亿[1]。糖尿病引发的心血管意外已成为患者死亡的主要原因,且死亡率明显高于非糖尿病患者[2]。糖尿病心肌病(diabetic cardiomyopathy, DCM)是一种因长期高... 糖尿病是一种慢性代谢性紊乱疾病。据统计,我国2021年糖尿病患者数量已高达1.41亿[1]。糖尿病引发的心血管意外已成为患者死亡的主要原因,且死亡率明显高于非糖尿病患者[2]。糖尿病心肌病(diabetic cardiomyopathy, DCM)是一种因长期高血糖引起的心脏结构和功能异常的疾病,与多种信号通路有关。 展开更多
关键词 o-连接N-乙酰葡萄糖胺 糖尿病心肌病 o-GlcNAc转移酶 o-GlcNAc水解酶
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O-抗原糖基转移酶对嗜水气单胞菌环境适应性及致病性的影响
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作者 裴建武 唐玉屏 +3 位作者 徐蒙 万夕和 董雨豪 刘永杰 《南京农业大学学报》 CAS CSCD 北大核心 2024年第6期1113-1121,共9页
[目的]本文旨在探究4种O-抗原糖基转移酶(glycosyltransferase,GT)对嗜水气单胞菌NJ-35环境适应性和毒力的影响。[方法]采用同源重组技术构建GT基因缺失株ΔGT-1、ΔGT-2、ΔGT-3和ΔGT-4,比较缺失株与野生株在体外生长、抗应激、抗吞... [目的]本文旨在探究4种O-抗原糖基转移酶(glycosyltransferase,GT)对嗜水气单胞菌NJ-35环境适应性和毒力的影响。[方法]采用同源重组技术构建GT基因缺失株ΔGT-1、ΔGT-2、ΔGT-3和ΔGT-4,比较缺失株与野生株在体外生长、抗应激、抗吞噬、细胞黏附能力、对斑马鱼毒力以及脂多糖(LPS)表达量等方面的差异。[结果]在含有20 g·L^(-1)NaCl的高渗LB(Luria-Bertani)培养基中,相比野生(WT)菌株,4个缺失株生长均未发生明显变化;在2 mmol·L^(-1)H _(2)O_(2)的强氧化应激条件下,4个缺失株抗氧化能力显著降低,特别是缺失株ΔGT-3存活率下降90%,ΔGT-4存活率下降86.5%,另外2株缺失株存活率下降近40%;在LB培养基(pH5.0)中作用30 min,4个缺失株存活率相比野生株均明显降低,其中ΔGT-3存活率下降近30%;4个缺失株对上皮细胞的黏附能力均显著降低,抗吞噬能力均显著增强;相比野生株,ΔGT-4对斑马鱼半数致死量(LD 50)上升近20倍,其他缺失株的毒力无明显变化;4个缺失株的LPS表达量均降低,且ΔGT-1和ΔGT-4的LPS最高分子质量条带出现缺失。[结论]O-抗原糖基转移酶有助于嗜水气单胞菌抵抗酸应激和氧化应激环境,并在该菌的黏附和毒力上发挥重要作用。 展开更多
关键词 嗜水气单胞菌 o-抗原糖基转移酶 环境适应性 毒力
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酯化酶甾醇O-酰基转移酶1在恶性肿瘤中作用的研究进展
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作者 王亮 黄幼生 +1 位作者 符谨诚 邹科见 《中国医药》 2024年第1期142-145,共4页
甾醇O-酰基转移酶1(SOAT1)是一种位于内质网内的酯化酶,催化细胞内游离胆固醇转化为脂滴。SOAT1被发现在多种恶性肿瘤内高表达,并与恶性肿瘤增殖、侵袭迁移紧密相关。这表明SOAT1有潜力成为恶性肿瘤早期诊断的生物标志物和治疗新靶点。... 甾醇O-酰基转移酶1(SOAT1)是一种位于内质网内的酯化酶,催化细胞内游离胆固醇转化为脂滴。SOAT1被发现在多种恶性肿瘤内高表达,并与恶性肿瘤增殖、侵袭迁移紧密相关。这表明SOAT1有潜力成为恶性肿瘤早期诊断的生物标志物和治疗新靶点。本文就SOAT1的结构、功能及其在恶性肿瘤中作用的相关研究进展进行综述。 展开更多
关键词 恶性肿瘤 甾醇o-酰基转移酶1 胆固醇 研究进展
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O-GlcNAc糖基化修饰在糖尿病性白内障中的作用
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作者 罗茜 杨聪聪 +1 位作者 景刘洁 张春巍 《国际眼科杂志》 CAS 2024年第12期1882-1887,共6页
目的:分析O-连接N-乙酰氨基葡萄糖(O-GlcNAc)修饰在年龄相关性白内障和糖尿病性白内障晶状体前囊膜中的表达变化,探讨O-GlcNAc糖基化修饰在糖尿病性白内障中的作用。方法:以糖尿病性白内障患者54例56眼和年龄相关性白内障患者115例120... 目的:分析O-连接N-乙酰氨基葡萄糖(O-GlcNAc)修饰在年龄相关性白内障和糖尿病性白内障晶状体前囊膜中的表达变化,探讨O-GlcNAc糖基化修饰在糖尿病性白内障中的作用。方法:以糖尿病性白内障患者54例56眼和年龄相关性白内障患者115例120眼的晶状体前囊膜为研究对象,利用免疫印迹技术检测年龄相关性和糖尿病性白内障晶状体前囊膜中O-GlcNAc蛋白的表达水平,富集晶状体前囊膜组织中O-GlcNAc糖蛋白并通过质谱方法鉴定两组样本晶状体前囊膜中O-GlcNAc差异蛋白的表达。结果:免疫印迹结果显示,糖尿病性白内障组晶状体前囊膜中O-GlcNAc蛋白表达水平显著高于年龄相关性白内障组(P<0.01),且随着糖化血红蛋白水平的升高,O-GlcNAc蛋白表达水平也升高(P<0.01)。我们采用质谱法对糖尿病性白内障和年龄相关性白内障晶状体前囊膜中O-GlcNAc蛋白进行差异分析,在糖尿病性白内障组中发现5种表达上调的O-GlcNAc蛋白(FABP5、KRT16、PGK1、CTSD、S100A7),18种表达下调的O-GlcNAc蛋白(CRYβB1等),同时我们还鉴定出3个新的O-GlcNAc糖基化修饰位点:蛋白质PTPRQ的T1730和S1738位的O-GlcNAc糖基化和蛋白质ATP5MC2的T61位的O-GlcNAc糖基化。结论:O-GlcNAc糖基化修饰可能参与了糖尿病性白内障的形成和发展。质谱鉴定出的O-GlcNAc差异蛋白为进一步研究糖尿病性白内障的发病机制提供了理论依据。 展开更多
关键词 o-连接N-乙酰氨基葡萄糖(o-GlcNAc)修饰 糖尿病性白内障 年龄相关性白内障 晶状体前囊膜 质谱
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A Planning Method for Operational Test of UAV Swarm Based on Mission Reliability
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作者 Jingyu Wang Ping Jiang Jianjun Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1889-1918,共30页
The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the... The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the high cost and long duration of operational tests,it is essential to plan the test in advance.To solve the problem of planning UAV swarm operational test,this study considers the multi-stage feature of a UAV swarm mission,composed of launch,flight and combat stages,and proposes a method to find test plans that can maximize mission reliability.Therefore,a multi-stage mission reliability model for a UAV swarm is proposed to ensure successful implementation of the mission.A multi-objective integer optimization method that considers both mission reliability and cost is then formulated to obtain the optimal test plans.This study first constructs a mission reliability model for the UAV swarm in the combat stage.Then,the launch stage and flight stage are integrated to develop a complete PMS(Phased Mission Systems)reliability model.Finally,the Binary Decision Diagrams(BDD)and Multi Objective Quantum Particle Swarm Optimization(MOQPSO)methods are proposed to solve the model.The optimal plans considering both reliability and cost are obtained.The proposed model supports the planning of UAV swarm operational tests and represents a meaningful exploration of UAV swarm test planning. 展开更多
关键词 UAV swarm PMS MOQPSO BDD mission reliability operational test planning
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Strategic Study on the Development of Space Science in China and Proposals for Future Missions
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作者 WANG Chi SONG Tingting +1 位作者 LI Ming CAO Song 《空间科学学报》 CAS CSCD 北大核心 2024年第4期699-703,共5页
Since 2011,the Chinese Academy of Sciences(CAS)has implemented the Strategic Priority Program on Space Science(SPP).A series of scientific satellites have been developed and launched,such as Dark Matter Particle Explo... Since 2011,the Chinese Academy of Sciences(CAS)has implemented the Strategic Priority Program on Space Science(SPP).A series of scientific satellites have been developed and launched,such as Dark Matter Particle Explorer(DAMPE),Quantum Experiments at Space Scale(QUESS),Advanced Space-based Solar Observatory(ASO-S),Einstein Probe(EP),and significant scientific outcomes have been achieved.In order to plan the future space science missions in China,CAS has organized the Chinese space science community to conduct medium and long-term development strategy studies,and summarized the major scientific frontiers of space science as“One Black,Two Dark,Three Origins and Five Characterizations”.Five main scientific themes have been identified for China’s future breakthroughs,including the Extreme Universe,Space-Time Ripples,the Panoramic View of the Sun and Earth,the Habitable Planets,and Biological&Physical Science in Space.Space science satellite missions to be implemented before 2030 are proposed accordingly. 展开更多
关键词 Space science Space missions Space exploration
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An Intelligent Framework for Resilience Recovery of FANETs with Spatio-Temporal Aggregation and Multi-Head Attention Mechanism
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作者 Zhijun Guo Yun Sun +2 位作者 YingWang Chaoqi Fu Jilong Zhong 《Computers, Materials & Continua》 SCIE EI 2024年第5期2375-2398,共24页
Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanne... Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanned Aerial Vehicle(UAV)swarms in harsh environments.This paper proposes an intelligent framework to quickly recover the cooperative coveragemission by aggregating the historical spatio-temporal network with the attention mechanism.The mission resilience metric is introduced in conjunction with connectivity and coverage status information to simplify the optimization model.A spatio-temporal node pooling method is proposed to ensure all node location features can be updated after destruction by capturing the temporal network structure.Combined with the corresponding Laplacian matrix as the hyperparameter,a recovery algorithm based on the multi-head attention graph network is designed to achieve rapid recovery.Simulation results showed that the proposed framework can facilitate rapid recovery of the connectivity and coverage more effectively compared to the existing studies.The results demonstrate that the average connectivity and coverage results is improved by 17.92%and 16.96%,respectively compared with the state-of-the-art model.Furthermore,by the ablation study,the contributions of each different improvement are compared.The proposed model can be used to support resilient network design for real-time mission execution. 展开更多
关键词 RESILIENCE cooperative mission FANET spatio-temporal node pooling multi-head attention graph network
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Life Origin in the Milky Way Galaxy: II. Scanning for Habitable Stellar Systems on Behalf of Future Space Missions
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作者 Alexander N. Safronov 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期681-692,共12页
The possibility of the life origin in the stellar systems, located at a distance of ~200 pc from the solar system, was investigated. The stars, in the spectrums of which C (carbon), O (oxygen), N (nitrogen), and P (ph... The possibility of the life origin in the stellar systems, located at a distance of ~200 pc from the solar system, was investigated. The stars, in the spectrums of which C (carbon), O (oxygen), N (nitrogen), and P (phosphorus) are found, are called DNA-stars. Based on stellar abundances a new method for searching for habitable exoplanets has been developed and a list of 48 DNA-stars in the solar neighborhood, on which life is possible, has been defined. The quota of DNA-stars is equal 1.3% of the total amount of Hypatia Stellar Catalog. Only three DNA-stars out of selected 48 stars belong to the spectral class as our Sun (G2V). The closest to the solar system is the DNA-star with the number HIP 15510, which belongs to the G8V class and is 6 pc away from the solar system. Nine DNA-stars, which have the highest chemical similarity with solar spectrum, were identified. It is identified that one of these nine stars, HIP 24681, has six planets. 展开更多
关键词 Interstellar mission Stellar Abundance HABITABILITY Hypatia Stellar Catalog DNA-Star
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Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network
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作者 YANG Luyi LI Haiyang +1 位作者 ZHANG Jin ZHU Yuehe 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期495-508,共14页
It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly eval... It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model. 展开更多
关键词 manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency
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保健食品中O-丙基羟基伐地那非的快速筛查、确证和定量测定
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作者 夏金涛 张莉 +3 位作者 吴婉琴 朱晓玲 蒋颖 江丰 《食品安全质量检测学报》 CAS 2024年第21期13-21,共9页
目的利用高分辨质谱仪快速筛查壮阳类保健食品中的磷酸二酯酶5型抑制剂(phosphodiesterase type 5 inhibitors,PDE-5i),确证其中发现的新型非法添加物并建立定量检测方法。方法采用超高效液相色谱-四级杆-飞行时间质谱仪(ultra performa... 目的利用高分辨质谱仪快速筛查壮阳类保健食品中的磷酸二酯酶5型抑制剂(phosphodiesterase type 5 inhibitors,PDE-5i),确证其中发现的新型非法添加物并建立定量检测方法。方法采用超高效液相色谱-四级杆-飞行时间质谱仪(ultra performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry,UPLC-Q-TOF/MS)对20批次保健食品中的非法添加物进行日常非靶向筛查,在2批次压片糖果中鉴别出一种新型伐地那非类似物。结合化合物的质谱裂解规律及核磁共振波谱(nuclear magnetic resonance spectrometry,NMR)对未知物结构进行确证。采用超高效液相色谱-三重四级杆质谱法(ultra performance liquid chromatography-coupled triple quadrupole mass spectrometry,UPLC-MS/MS)建立了典型食品基质中未知物的定量检测方法。结果未知物被确证为O-丙基羟基伐地那非。该物质溶剂校准和基质匹配曲线在2~100 ng/mL质量浓度范围内线性关系良好,相关系数(r2)大于0.995,检出限为0.05 mg/kg,定量限为0.10 mg/kg。在固体饮料、压片糖果、果冻基质中3个水平加标回收率为94.45%~104.16%,相对标准偏差(relative standard deviation,RSD)为0.70%~4.02%。采用该方法测得2批次阳性样品中O-丙基羟基伐地那非的含量分别为22.0 mg/kg、13.8 g/kg。结论本方法适用于食品中那非类似物的快速筛查,用于O-丙基羟基伐地那非的定量检测高效、灵敏、准确。本研究为食品基质中非法添加物的系统性确证和定量研究提供了可供借鉴的参考模型。 展开更多
关键词 快速筛查 结构确证 定量测定 非法添加物 o-丙基羟基伐地那非
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食品中一种新型非法添加物O-丙基伐地那非的快速筛查和定量测定 被引量:1
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作者 饶雅琨 王苑桃 +5 位作者 孙晓 王涛 董曼曼 李旸 李荣 张亚锋 《食品安全质量检测学报》 CAS 2024年第6期228-235,共8页
目的对在食品中发现的一种非法添加的新型磷酸二酯酶5型(phosphodiesterase type 5,PDE-5)抑制剂O-丙基伐地那非进行结构解析并建立定量测定方法。方法采用高效液相色谱-二极管阵列检测器法(high performance liquid chromatography-dio... 目的对在食品中发现的一种非法添加的新型磷酸二酯酶5型(phosphodiesterase type 5,PDE-5)抑制剂O-丙基伐地那非进行结构解析并建立定量测定方法。方法采用高效液相色谱-二极管阵列检测器法(high performance liquid chromatography-diode array detector,HPLC-DAD)发现了一种未知的新型伐地那非类似物,采用超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry,UPLC-Q-Orbitrap HRMS)对其结构进行质谱解析,并依据解析的化学结构购买对照品,确定该物质为O-丙基伐地那非。采用超高效液相色谱-三重四极杆质谱法(ultra performance liquid chromatography-coupled triple quadrupole mass spectrometry,UPLC-MS/MS)建立典型食品中O-丙基伐地那非的定量测定方法。结果O-丙基伐地那非在0.50~50.25 ng/mL质量浓度范围内线性关系良好,相关系数(r)为0.9998,方法检出限(S/N=3)为0.02mg/kg,方法的定量限(S/N=10)为0.05mg/kg,在咖啡、压片糖果、保健酒基质中3个水平加样回收率分别为91.8%~93.9%、84.9%~87.3%和95.6%~103.0%,相对标准偏差均不大于4.6%。采用该方法对市场监管部门送检的93批样品进行测定,结果其中17批检出O-丙基伐地那非,其含量为28~359 mg/kg。结论所建立的方法快速、灵敏、准确,可用于O-丙基伐地那非的筛查和定量。本研究思路可给其他非法添加未知物的鉴定提供参考。 展开更多
关键词 超高效液相色谱-四极杆-静电场轨道阱质谱法 超高效液相色谱-三重四极杆质谱法 非法添加 o-丙基伐地那非 伐地那非衍生物
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O,O-二烷基硫代磷酰氯制备过程中一氯化硫处理进展
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作者 王振州 刘伟 +3 位作者 李敏 曾雪云 陈灿 陈明 《精细化工中间体》 CAS 2024年第1期1-8,共8页
O,O-二烷基硫代磷酰氯是一种重要的农药中间体,可用于制备多种有机磷类杀虫剂。基于五硫化二磷合成O,O-二烷基硫代磷酰氯是目前研究热点,综述了以五硫化二磷为原料合成O,O-二烷基硫代磷酰氯过程中一氯化硫的处理方法,并分析了各种方法... O,O-二烷基硫代磷酰氯是一种重要的农药中间体,可用于制备多种有机磷类杀虫剂。基于五硫化二磷合成O,O-二烷基硫代磷酰氯是目前研究热点,综述了以五硫化二磷为原料合成O,O-二烷基硫代磷酰氯过程中一氯化硫的处理方法,并分析了各种方法的优缺点。 展开更多
关键词 O o-二烷基硫代磷酰氯 一氯化硫 胶体硫 五硫化二磷
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固醇O-酰基转移酶1在肿瘤中的研究进展
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作者 马媛媛 郑振鲁 +1 位作者 徐辉 高小玲 《癌症进展》 2024年第7期706-710,718,共6页
固醇O-酰基转移酶1(SOAT1),又称为酰基辅酶A、胆固醇酰基转移酶1(ACAT1),是胆固醇酯化途径中至关重要的酶,其可将内质网中的胆固醇转化为胆固醇酯,随后储存于脂滴中,以维持细胞内脂质代谢平衡。研究发现,SOAT1不仅与动脉粥样硬化和阿尔... 固醇O-酰基转移酶1(SOAT1),又称为酰基辅酶A、胆固醇酰基转移酶1(ACAT1),是胆固醇酯化途径中至关重要的酶,其可将内质网中的胆固醇转化为胆固醇酯,随后储存于脂滴中,以维持细胞内脂质代谢平衡。研究发现,SOAT1不仅与动脉粥样硬化和阿尔茨海默病等的发生发展密切相关,还在促进肿瘤发生发展中发挥重要作用。在多种肿瘤中,SOAT1高表达与患者的预后不良密切相关,SOAT1被认为可能成为多种肿瘤患者预后的生物标志物和治疗靶点。本文对SOAT1的结构功能及其在肿瘤中的作用进行综述,以期为SOAT1的进一步研究及临床应用提供参考。 展开更多
关键词 固醇o-酰基转移酶1 胆固醇 胆固醇酯 肿瘤
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“Einstein Probe”Mission Holds New Promise in Time-domain Astronomy
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作者 SONG Jianlan 《Bulletin of the Chinese Academy of Sciences》 2024年第1期8-10,共3页
Einstein Probe,an astronomical satellite designed for X-ray observation on astronomical events drastically evolving over time,was successfully sent into preset orbit by a Long March 2C rocket from China’s Xichang Sat... Einstein Probe,an astronomical satellite designed for X-ray observation on astronomical events drastically evolving over time,was successfully sent into preset orbit by a Long March 2C rocket from China’s Xichang Satellite Launch Center located in Sichuan Province at 15:03 GMT+8 on January 9,2024. 展开更多
关键词 PROBE PROMISE mission
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蛋白质O-连接-N-乙酰葡萄糖胺修饰在心力衰竭中的作用的研究进展
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作者 张小雪 王汶芳 王占黎 《大医生》 2024年第8期11-14,共4页
蛋白质O-连接-N-乙酰葡萄糖胺(O-GlcNAc)修饰是细胞内普遍存在的重要蛋白质翻译后修饰,对于细胞生物学功能至关重要。这种翻译后修饰可影响细胞的翻译与转运,对维持和促进正常细胞发挥功能有重要意义。蛋白质O-GlcNAc修饰对心脏组织有... 蛋白质O-连接-N-乙酰葡萄糖胺(O-GlcNAc)修饰是细胞内普遍存在的重要蛋白质翻译后修饰,对于细胞生物学功能至关重要。这种翻译后修饰可影响细胞的翻译与转运,对维持和促进正常细胞发挥功能有重要意义。蛋白质O-GlcNAc修饰对心脏组织有重要作用,短期内增加的蛋白质O-GlcNAc对心脏有保护作用,而长期增加的蛋白质O-GlcNAc导致心脏功能障碍。蛋白质O-GlcNAc修饰在心血管疾病中的辅助治疗作用已成为当前研究热点。现就蛋白质O-GlcNAc修饰在心力衰竭中的作用的研究进展进行综述。 展开更多
关键词 o-连接-N-乙酰葡萄糖胺 心力衰竭 心脏保护
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具有PDA-UiO-66中间层耐溶剂复合纳滤膜的制备及性能 被引量:1
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作者 李浪 李新冬 +2 位作者 李海柯 李文豪 黄万抚 《精细化工》 EI CAS CSCD 北大核心 2023年第2期388-397,共10页
将多巴胺和Ui O-66纳米颗粒共沉积在经1,6-己二胺交联的聚醚酰亚胺(PEI)基膜上构建了纳米复合中间层(PDA-UiO-66),并在中间层上进行界面聚合反应制备了耐溶剂复合纳滤膜(TFN-U)。通过FTIR、XRD、SEM、AFM、水接触角测量仪对膜结构进行... 将多巴胺和Ui O-66纳米颗粒共沉积在经1,6-己二胺交联的聚醚酰亚胺(PEI)基膜上构建了纳米复合中间层(PDA-UiO-66),并在中间层上进行界面聚合反应制备了耐溶剂复合纳滤膜(TFN-U)。通过FTIR、XRD、SEM、AFM、水接触角测量仪对膜结构进行了表征和测试,探究了Ui O-66质量浓度对TFN-U膜耐溶剂性、耐污染性以及运行稳定性的影响。结果表明,PDA-Ui O-66纳米复合中间层的引入能提高TFN-U膜的渗透通量,当Ui O-66纳米颗粒质量浓度为0.2 g/L时,TFN-U2膜水通量为63.83 L/(m^(2)·h),甲醇通量为28.50L/(m^(2)·h),对刚果红水溶液和刚果红甲醇溶液的截留率为98.2%和93.2%,经无水乙醇、丙酮、乙酸乙酯、正己烷及N,N-二甲基甲酰胺(DMF)浸泡48h后,其对刚果红的截留率均>94%,通量恢复率达到78.1%,在连续24 h过滤刚果红甲醇溶液后,该膜的甲醇通量为14.13L/(m^(2)·h),截留率为98.3%,表明TFN-U2膜具有良好的耐溶剂性、耐污染性以及一定的运行稳定性。 展开更多
关键词 聚多巴胺 Ui o-66 中间层 耐溶剂 复合纳滤膜 水处理技术
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Mission reliability modeling and evaluation for reconfigurable unmanned weapon system-of-systems based on effective operation loop 被引量:1
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作者 CHEN Zhiwei ZHOU Ziming +2 位作者 ZHANG Luogeng CUI Chaowei ZHONG Jilong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期588-597,共10页
The concept of unmanned weapon system-of-systems(UWSoS)involves a collection of various unmanned systems to achieve or accomplish a specific goal or mission.The mission reliability of UWSoS is represented by its abili... The concept of unmanned weapon system-of-systems(UWSoS)involves a collection of various unmanned systems to achieve or accomplish a specific goal or mission.The mission reliability of UWSoS is represented by its ability to finish a required mission above the baselines of a given mission.However,issues with heterogeneity,cooperation between systems,and the emergence of UWSoS cannot be effectively solved by traditional system reliability methods.This study proposes an effective operation-loop-based mission reliability evaluation method for UWSoS by analyzing dynamic reconfiguration.First,we present a new connotation of an effective operation loop by considering the allocation of operational entities and physical resource constraints.Then,we propose an effective operationloop-based mission reliability model for a heterogeneous UWSoS according to the mission baseline.Moreover,a mission reliability evaluation algorithm is proposed under random external shocks and topology reconfiguration,revealing the evolution law of the effective operation loop and mission reliability.Finally,a typical 60-unmanned-aerial-vehicle-swarm is taken as an example to demonstrate the proposed models and methods.The mission reliability is achieved by considering external shocks,which can serve as a reference for evaluating and improving the effectiveness of UWSoS. 展开更多
关键词 mission reliability unmanned weapon system-ofsystems dynamic reconfiguration effective operation loop
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Spatio-Temporal Polar-Inclined Space Mission Architecture for a Refined Retrieve of the Earth’s Gravity Field
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作者 Basem Elsaka 《World Journal of Engineering and Technology》 2019年第4期640-651,共12页
Future satellite gravity missions (FGMs) have been intensively studied during the last recent years for the era beyond the successful previous GRACE and current GRACE Follow-on satellite missions. Previous studies hav... Future satellite gravity missions (FGMs) have been intensively studied during the last recent years for the era beyond the successful previous GRACE and current GRACE Follow-on satellite missions. Previous studies have investigated the gravity field recovery derived from combined two satellite-pairs (referred here as PI-FGM, a single polar satellite-pair like the GRACE mission combined with another inclined satellite-pair) with different orbital heights of few kilometers and different repeat orbital periods. In this contribution, new innovative idea is introduced by designing the inclined satellite-pair of the FGM at the same orbital height of the polar-type with shifted spatio-temporal (ST-FGM) orbital parameters to avoid any possible collision risk between the two satellite-pairs, polar and inclined, of the FGM architecture. The repeat orbits issue will be taken into consideration through the manuscript and will be set as identical as possible for a fair comparison. The findings through a full-scale simulation analysis show that the new design of shifted spatio-temporal polar-inclined (ST-FGM) mission architecture basically outperforms the two satellite-pairs having different orbital heights (i.e. the PI-FGM mission configuration). Regarding the gravity field recovery, the ST-FGM architecture retrieves the geoid heights with standard deviations of about 17.0 mm providing more isotropic error distribution. An overall improvement by a factor of about 80 and 60 is provided by the ST-FGM and PI-FGM mission architectures, respectively, with respect to the GRACE-like formation and a factor of about 2.4 and 1.8, respectively, with respect to the smoothed gravity solution using the Gaussian filter at radius 400 km. Therefore, the shifted spatio-temporal polar-inclined (ST-FGM) is worthy recommended as stable mission architecture and would be considered as one of the future gravity missions. 展开更多
关键词 Space mission Architectures ORBIT Design REPEAT ORBIT Gravity Field Recovery FULL-SCALE Simulation
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Estimation of far-field wavefront error of tilt-to-length distortion coupling in space-based gravitational wave detection 被引量:1
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作者 陶雅正 金洪波 吴岳良 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期20-26,共7页
In space-based gravitational wave detection, the estimation of far-field wavefront error of the distorted beam is the precondition for the noise reduction. Zernike polynomials are used to describe the wavefront error ... In space-based gravitational wave detection, the estimation of far-field wavefront error of the distorted beam is the precondition for the noise reduction. Zernike polynomials are used to describe the wavefront error of the transmitted distorted beam. The propagation of a laser beam between two telescope apertures is calculated numerically. Far-field wavefront error is estimated with the absolute height of the peak-to-valley phase deviation between the distorted Gaussian beam and a reference distortion-free Gaussian beam. The results show that the pointing jitter is strongly related to the wavefront error. Furthermore, when the jitter decreases 10 times from 100 nrad to 10 nrad, the wavefront error reduces for more than an order of magnitude. In the analysis of multi-parameter minimization, the minimum of wavefront error tends to Z[5,3] Zernike in some parameter ranges. Some Zernikes have a strong correlation with the wavefront error of the received beam. When the aperture diameter increases at Z[5,3] Zernike, the wavefront error is not monotonic and has oscillation.Nevertheless, the wavefront error almost remains constant with the arm length increasing from 10-1Mkm to 10~3Mkm.When the arm length decreases for three orders of magnitude from 10-1Mkm to 10-4Mkm, the wavefront error has only an order of magnitude increasing. In the range of 10-4Mkm to 10~3Mkm, the lowest limit of the wavefront error is from 0.5 fm to 0.015 fm at Z[5,3] Zernike and 10 nrad jitter. 展开更多
关键词 laser optical systems space mission gravitational wave
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Joint mission and route planning of unmanned air vehicles via a learning-based heuristic 被引量:1
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作者 SHI Jianmai ZHANG Jiaming +2 位作者 LEI Hongtao LIU Zhong WANG Rui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期81-98,共18页
Unmanned air vehicles(UAVs) have been regularly employed in modern wars to conduct different missions. Instead of addressing mission planning and route planning separately,this study investigates the issue of joint mi... Unmanned air vehicles(UAVs) have been regularly employed in modern wars to conduct different missions. Instead of addressing mission planning and route planning separately,this study investigates the issue of joint mission and route planning for a fleet of UAVs. The mission planning determines the configuration of weapons in UAVs and the weapons to attack targets, while the route planning determines the UAV’s visiting sequence for the targets. The problem is formulated as an integer linear programming model. Due to the inefficiency of CPLEX on large scale optimization problems, an effective learningbased heuristic, namely, population based adaptive large neighborhood search(P-ALNS), is proposed to solve the model. In P-ALNS, seven neighborhood structures are designed and adaptively utilized in terms of their historical performance. The effectiveness and superiority of the proposed model and algorithm are demonstrated on test instances of small, medium and large sizes. In particular, P-ALNS achieves comparable solutions or as good as those of CPLEX on small-size(20 targets)instances in much shorter time. 展开更多
关键词 unmanned air vehicle(UAV) mission planning ROUTING adaptive large neighborhood search
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