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Applied mathematics and Mechanics(English Edition) 2020年第5期41卷 805-818页

作者： Weichao CHI S.j.ma j.Q.SUN College of Science Northeastern UniversityShenyang 100819China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 100819China Department of Mechanical Engineering School of EngineeringUniversity of CaliforniaMercedCA 95343U.S.A.

The hybrid vibration isolation, which takes advantages of both the passive and active approaches, has been an important solution for space missions. The objective of this paper is to design a vibration isolation platform for payloads on spacecrafts with the robust, wide bandwidth, and multi-degree-of-freedom(MDOF). The proposed solution is based on a parallel mechanism with six voice-coil motors(VCMs) as the actuators. The linear active disturbance resistance control(LADRC) algorithm is used for the active control. Numerical simulation results show that the vibration isolation platform performs effectively over a wide bandwidth, and the resonance introduced by the passive isolation is eliminated. The system robustness to the uncertainties of the structure is also verified by simulation.

关键词： hybrid vibration isolation Stewart platform linear active disturbance rejection control(LADRC) stability robustness

Adeno-associated virus as a delivery vector for gene therapy of human diseases

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1808-1840页

作者： jiang-Hui Wang Dominic j.Gessler Wei Zhan Thomas L.Gallagher Guangping Gao Horae Gene Therapy Center University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Department of Microbiology and physiological Systems University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Centre for Eye Research Australia Royal Victorian Eye and Ear HospitalEast MelbourneVIC3002Australia Ophthalmology Department of SurgeryUniversity of MelbourneEast MelbourneVIC3002Australia Department of Neurological Surgery University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Department of Neurosurgery University of MinnesotaMinneapolisMN55455USA Department of Medicine University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Li Weibo Institute for Rare Diseases Research University of Massachusetts Chan Medical SchoolWorcesterMA01605USA

Adeno-associated virus(AAV)has emerged as a pivotal delivery tool in clinical gene therapy owing to its minimal pathogenicity and ability to establish long-term gene expression in different *** AAV(rAAV)has been engineered for enhanced specificity and developed as a tool for treating various ***,as rAAV is being more widely used as a therapy,the increased demand has created challenges for the existing manufacturing *** rAAV-based gene therapy products have received regulatory approval,but there continue to be concerns about safely using high-dose viral therapies in humans,including immune responses and adverse effects such as genotoxicity,hepatotoxicity,thrombotic microangiopathy,and *** this review,we explore AAV biology with an emphasis on current vector engineering strategies and manufacturing *** discuss how rAAVs are being employed in ongoing clinical trials for ocular,neurological,metabolic,hematological,neuromuscular,and cardiovascular diseases as well as *** outline immune responses triggered by rAAV,address associated side effects,and discuss strategies to mitigate these *** hope that discussing recent advancements and current challenges in the field will be a helpful guide for researchers and clinicians navigating the ever-evolving landscape of rAAV-based gene therapy.

关键词： diseases specificity approval

Quantifying the parameter dependent basin of the unsafe regime of asymmetric Lévy-noise-induced critical transitions

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Applied mathematics and Mechanics(English Edition) 2021年第1期42卷 65-84页

作者： jinzhong ma Yong XU Yongge LI Ruilan TIAN Shao juan ma j.KURTHS School of mathematical Sciences Shanxi UniversityTaiyuan 030000China Department of Applied mathematics Northwestern Polytechnical UniversityXi’an 710072China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi’an 710072China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of mathematics&Information Science North Minzu UniversityYinchuan 750021China potsdam Institute for Climate Impact Research Potsdam 14412Germany Department of physics Humboldt University at BerlinBerlin 12489Germany

In real systems,the unpredictable jump changes of the random environment can induce the critical transitions(CTs)between two non-adjacent states,which are more *** an asymmetric Lévy-noise-induced tri-stable model with desirable,sub-desirable,and undesirable states as a prototype class of real systems,a prediction of the noise-induced CTs from the desirable state directly to the undesirable one is carried *** first calculate the region that the current state of the given model is absorbed into the undesirable state based on the escape probability,which is named as the absorbed ***,a new concept of the parameter dependent basin of the unsafe regime(pDBUR)under the asymmetric Lévy noise is *** is an efficient tool for approximately quantifying the ranges of the parameters,where the noise-induced CTs from the desirable state directly to the undesirable one may *** importantly,it may provide theoretical guidance for us to adopt some measures to avert a noise-induced catastrophic CT.

关键词： tri-stable model asymmetric Lévy noise critical transition(CT) escape probability absorbed region parameter dependent basin of unsafe regime(pDBUR)

调质处理对1000 Mpa级水电用钢组织性能的影响

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材料热处理学报 2024年第9期45卷 176-183,191页

作者：肖桂枝杨继学安茹马金磊麻衡西安建筑科技大学冶金工程学院陕西西安710055 莱芜钢铁集团银山型钢有限公司山东济南271104

利用扫描电镜、透射电镜、拉伸和冲击试验机等研究了不同调质处理工艺对1000 Mpa级水电用钢微观组织和力学性能的影响。结果表明:淬火后的实验钢组织呈准等轴状,板条马氏体组织细小。在890~950℃淬火温度范围内,随着淬火温度的升高,马... 详细信息

利用扫描电镜、透射电镜、拉伸和冲击试验机等研究了不同调质处理工艺对1000 Mpa级水电用钢微观组织和力学性能的影响。结果表明:淬火后的实验钢组织呈准等轴状,板条马氏体组织细小。在890~950℃淬火温度范围内,随着淬火温度的升高,马氏体板条束尺寸增加,经过620℃回火后组织转变为回火索氏体,回火过程中碳化物的析出及其与位错的交互作用提高了实验钢的强度。随淬火温度升高,实验钢的屈服强度和抗拉强度增加,伸长率基本保持不变,-60℃冲击吸收能量呈现先缓慢增加后急剧减小的趋势,冲击断裂方式由韧性断裂转变为脆性解理断裂。经920℃×30 min+620℃×60 min调质工艺处理后,实验钢的屈服强度、抗拉强度、伸长率及-60℃冲击吸收能量分别为970 Mpa、986 Mpa、15%和185 j,其综合力学性能达到最优,满足1000 Mpa级水电用钢的性能要求。

关键词：水电用钢调质处理微观结构演化力学性能强化机理

单细胞测序分析病毒性肺炎患者T细胞受体基因差异

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中国免疫学杂志 2024年第4期40卷 796-801页

作者：马恩泽宁可朱晓哈尔滨师范大学计算机科学与信息工程学院哈尔滨150025 烟台大学计算机与控制工程学院烟台264005

目的:采用单细胞测序分析病毒性肺炎患者外周血T细胞受体(TCR)基因差异,探讨可能发病机制。方法:利用NCBI数据库获得数据,设置病例组和对照组进行实验。使用RStudio软件R语言分析单细胞测序数据,绘制表格和图片,得出结论。结果:病例组... 详细信息

目的:采用单细胞测序分析病毒性肺炎患者外周血T细胞受体(TCR)基因差异,探讨可能发病机制。方法:利用NCBI数据库获得数据,设置病例组和对照组进行实验。使用RStudio软件R语言分析单细胞测序数据,绘制表格和图片,得出结论。结果:病例组和对照组TCR有显著差异。对TCRα链和β链V、j基因片段使用频率进行分析,其中病例组TRAV1-2、TRAV29/DV5、TRAj33、TRAj48、TRBV20-1、TRBV2、TRBj2-3、TRBj1-1等基因使用频率明显高于对照组(pj基因组合分析显示,病例组α链V-j对使用频率最高的是TRAV1-2-j33,β链V-j使用频率最高的是TRBV20-1-j2-1,αβ双链V-j使用频率最高的是TRAV30-j24-TRBV3-1-j2-7。结论:病毒性肺炎患者外周血TCR基因发生了明显改变,可能与病毒免疫发病机制有关。

关键词：单细胞测序病毒性肺炎 T细胞受体基因

2000-2021年新疆植被覆盖度变化及驱动力

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水土保持研究 2024年第1期31卷 385-394页

作者：马楠白涛蔡朝朝新疆农业大学计算机与信息工程学院乌鲁木齐830052 新疆农业信息化工程技术研究中心乌鲁木齐830052

[目的]探讨2000—2021年新疆植被覆盖变化及其驱动力的分析,为新疆地区环境监测提供理论依据。[方法]借助GEE平台获取由NASA提供的NDVI数据,利用趋势分析、Hurst指数法对新疆地区2000—2021年植被覆盖变化进行动态分析,结合气象等数据,... 详细信息

[目的]探讨2000—2021年新疆植被覆盖变化及其驱动力的分析,为新疆地区环境监测提供理论依据。[方法]借助GEE平台获取由NASA提供的NDVI数据,利用趋势分析、Hurst指数法对新疆地区2000—2021年植被覆盖变化进行动态分析,结合气象等数据,采用mann-Kendall、偏相关分析法等对植被覆盖变化与气候、地表因素的响应进行分析。[结果](1)2000—2021年新疆地区NDVI年际变化总体以0.0014/a的速率波动式增长;年内变化总体呈倒U型,草甸植被的NDVI月均值波动最大。(2)2000—2021年新疆地区NDVI年均值77.9%在0~0.3波动,在空间分布表现为北部和西北部高,南部和东南部低。(3)2000—2021年新疆地区总体slope值在-0.036~0.052波动,主要变化趋势为基本不变和轻微改善,结合Hurst指数,新疆植被主要未来趋势变化为改善到退化。(4)22年间新疆地区的气温总体呈上升趋势,降水、土壤湿度和径流总体呈下降趋势。NDVI年均值与气温、降水、土壤湿度和径流呈显著负相关性的像元数占比均大于正相关性的像元数占比,且存在明显的空间地域特征。[结论]新疆植被覆盖变化总体呈上升趋势,但未来趋势不容乐观,需要重点关注新疆地区的环境监测等保护措施。

关键词：植被类型 NDVI 趋势变化气温降水土壤湿度径流

县域治理中的“关系”逻辑——基于j县迎接“后评估”考核中“关系”运用的观察

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社会主义研究 2024年第4期 115-123页

作者：黄辉祥马恺阳华中师范大学政治与国际关系学院

关系作为一种特殊文化现象与实践方式,在国家治理与日常生活中都起着重要作用。县域治理作为国家治理的“接点”,连接城乡两端,因而“关系”运作在这一场域中更为突出和典型。在此背景下,本文以j县在巩固脱贫成果“后评估”考核中“督... 详细信息

关系作为一种特殊文化现象与实践方式,在国家治理与日常生活中都起着重要作用。县域治理作为国家治理的“接点”,连接城乡两端,因而“关系”运作在这一场域中更为突出和典型。在此背景下,本文以j县在巩固脱贫成果“后评估”考核中“督察—迎检”的互动过程为案例,深入分析县域治理主体试图通过“关系”运作以增强治理乡土社会的弹性空间的实践行为。研究发现,县域治理中的“关系”运作呈现为党政关系、县乡关系、条块关系和人际关系四个方面的实践样态,这些关系样态总体上呈现为正式关系与非正式关系交织的运作特征,进一步又可细究为公共关系与私人关系的混合、庇护关系与依附关系的共存、情感性关系与工具性关系的平衡的特征。体制因素、文化因素、制度因素和利益因素使这些“关系”能够不断被再生产出来,并通过运作和转化形塑着治理主体的行为。

关键词：县域治理国家治理基层政府乡土社会

致密储层差异化成岩作用及其对烃类充注过程的影响——以鄂尔多斯盆地延安地区下二叠统山西组1段为例

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天然气地球科学 2024年第10期35卷 1777-1788页

作者：郭兰郭顺丁超马志武延长油田股份有限公司陕西延安716000 陕西延长石油(集团)有限责任公司资源与勘探开发部陕西西安710075 西安石油大学地球科学与工程学院陕西西安710065 西安石油大学陕西省油气成藏地质学重点实验室陕西西安710065

针对鄂尔多斯盆地非常规天然气勘探亟待解决的关键地质问题,揭示储层成岩致密化与油气充注的动态过程和关系,利用铸体薄片观察、X射线衍射、扫描电镜分析,细致对比不同类型岩石相的成岩作用类型及特征的差异性。通过流体包裹体岩相学、... 详细信息

针对鄂尔多斯盆地非常规天然气勘探亟待解决的关键地质问题,揭示储层成岩致密化与油气充注的动态过程和关系,利用铸体薄片观察、X射线衍射、扫描电镜分析,细致对比不同类型岩石相的成岩作用类型及特征的差异性。通过流体包裹体岩相学、显微测温及激光拉曼探针测试,结合单井埋藏史和热史模拟,确定烃类充注期次和年代。综合利用成岩矿物间及与烃类间镜下结构关系观察,建立含气储层成岩—油气充注演化序列。结果表明:山西组1段主要发育2期烃类充注,第一期发生在晚三叠世—早、中侏罗世(220~170 ma),第二期发生在晚侏罗世—早白垩世(160~100 ma)。不同类型岩石的成岩作用、致密化过程及其与烃类充注的序列明显存在差异,富石英贫塑性岩屑砂岩在第二期烃类充注前物性较好,中成岩阶段烃类充注时边致密边成藏,富塑性岩屑砂岩早成岩阶段已基本被压实,而碳酸盐致密胶结砂岩由于方解石和菱铁矿的形成,储层致密化导致第二期烃类无法进入。深入理解致密储层差异成岩过程与油气充注关系,对筛选天然气有利区具有重要意义。

关键词：延安地区山西组非常规储层成岩演化成藏时序

基于多特征提取和麻雀搜索算法优化XGBoost的变压器绕组松动诊断方法

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电机与控制学报 2024年第6期28卷 87-97页

作者：马宏忠肖雨松颜锦孙永腾河海大学能源与电气学院江苏南京211100 国网湖南省电力有限公司衡阳供电分公司湖南衡阳421200

针对使用单一特征量诊断变压器绕组松动,在不同负载条件下存在交叠和抗干扰能力不足的问题,提出一种基于核主成分分析(KpCA)和改进麻雀搜索算法(SSA)优化极端梯度提升(XGBoost)的变压器绕组松动振动诊断方法。首先,从时域、频域和熵值3... 详细信息

针对使用单一特征量诊断变压器绕组松动,在不同负载条件下存在交叠和抗干扰能力不足的问题,提出一种基于核主成分分析(KpCA)和改进麻雀搜索算法(SSA)优化极端梯度提升(XGBoost)的变压器绕组松动振动诊断方法。首先,从时域、频域和熵值3个维度提取适用于变压器多传感器振动信号的多种特征量;其次,通过网格搜索优化的KpCA对特征量进行降维;最后,构建基于XGBoost的故障诊断模型,并采用改进麻雀搜索算法调参,实现不同电流大小下变压器绕组松动故障准确识别。以某110 kV变压器为对象进行实验验证,诊断结果表明,所提取的特征量能够准确反映故障特征,抗干扰能力更强,诊断模型故障诊断准确率为99.00%,相比于其他诊断算法准确率和稳定性更高,在不同负载情况下均有良好的识别效果。

关键词：变压器振动绕组松动核主成分分析极端梯度提升麻雀搜索算法故障诊断

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Mixed iridium-nickel oxides supported on antimony-doped tin oxide as highly efficient and stable acidic oxygen evolution catalysts

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materials Futures 2024年第1期3卷 165-180页

作者： jonathan Ruiz Esquius Alec p LaGrow Haiyan jin Zhipeng Yu Ana Araujo Rita marques Adélio Mendes Lifeng Liu Clean Energy Cluster International Iberian Nanotechnology LaboratoryAv.Mestre JoséVeigaBraga 4715-330Portugal Carbon Science and Technology Institute INCAR-CSICFrancisco Pintado Fe 26Oviedo 33011Spain Scientific Imaging Section Okinawa Institute of Science and Technology Graduate UniversityKunigami-gunOkinawa 904-0412Japan Songshan Lake materials Laboratory Dongguan 523808People’s Republic of China Laboratory for process Engineering EnvironmentBiotechnology and EnergyFaculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal Associate Laboratory in Chemical Engineering Faculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal.

proton exchange membrane(pEM)water electrolysis represents a promising technology for green hydrogen production,but its widespread deployment is greatly hindered by the indispensable usage of platinum group metal catalysts,especially iridium(Ir)based materials for the energy-demanding oxygen evolution reaction(OER).Herein,we report a new sequential precipitation approach to the synthesis of mixed Ir-nickel(Ni)oxy-hydroxide supported on antimony-doped tin oxide(ATO)nanoparticles(IrNiyO_(x)/ATO,20 wt.%(Ir+Ni),y=0,1,2,and 3),aiming to reduce the utilisation of scarce and precious Ir while maintaining its good acidic OER *** tested in strongly acidic electrolyte(0.1 M HClO_(4)),the optimised IrNi1Ox/ATO shows a mass activity of 1.0 maµgIr^(−1) and a large turnover frequency of 123 s^(−1) at an overpotential of 350 mV,as well as a comparatively small Tafel slope of 50 mV dec^(−1),better than the IrOx/ATO control,particularly with a markedly reduced Ir loading of only 19.7µgIr cm^(−2).Importantly,IrNi1O_(x)/ATO also exhibits substantially better catalytic stability than other reference catalysts,able to continuously catalyse acidic OER at 10 ma cm^(−2) for 15 h without obvious *** in-situ synchrotron-based x-ray absorption spectroscopy confirmed that the Ir^(3+)/Ir^(4+)species are the active sites for the acidic ***,the performance of IrNi1Ox/ATO was also preliminarily evaluated in a membrane electrode assembly,which shows better activity and stability than other reference *** IrNi1Ox/ATO reported in this work is a promising alternative to commercial IrO_(2) based catalysts for pEM electrolysis.

关键词： mixed oxides oxygen evolution reaction polymer electrolyte membrane antimony doped tin oxide membrane electrode assembly