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miRNA-208a-3p过表达致慢性心衰大鼠心肌细胞线粒体钙超载和功能障碍的机制研究
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作者 马丽娟 周祁娜 +4 位作者 张健 朱嘉俊 王宝珠 段明军 李发鹏 《新疆医科大学学报》 CAS 2024年第6期791-797,共7页
目的观察miRNA-208a-3p在慢性心力衰竭大鼠心肌中的表达水平,探讨其在线粒体钙稳态和线粒体功能方面的调节机制。方法35只健康SD大鼠,随机分为模型组(n=20)和对照组(n=15),模型组采用腹主动脉直径缩窄法建立慢性心衰模型,对照组行假手... 目的观察miRNA-208a-3p在慢性心力衰竭大鼠心肌中的表达水平,探讨其在线粒体钙稳态和线粒体功能方面的调节机制。方法35只健康SD大鼠,随机分为模型组(n=20)和对照组(n=15),模型组采用腹主动脉直径缩窄法建立慢性心衰模型,对照组行假手术。通过心功能和组织病理学检测评价模型,测定心肌miR-208a-3p表达,心肌线粒体去乙酰化酶3(SIRT3)蛋白和NADH脱氢酶亚基1(ND1)蛋白表达、线粒体Ca2+水平、心肌细胞活性氧(ROS)生成。结果模型组大鼠心肌miR-208a-3p表达水平显著高于对照组(P<0.05),SIRT3蛋白表达显著低于对照组(P<0.001),且miR-208a-3p与SIRT3表达呈显著负相关;模型组ND1蛋白表达显著低于对照组(P<0.05),且ND1与SIRT3表达呈显著正相关;模型组心肌细胞线粒体内Ca2+水平显著高于对照组(P<0.05),心肌细胞ROS生成也显著高于对照组(P<0.05)。结论慢性心衰心肌组织miR-208a-3p过度表达与SIRT3/ND1活性降低相关,抑制线粒体呼吸链活性,此外,心肌细胞出现线粒体钙超载和ROS生成增加,进一步加剧线粒体呼吸功能障碍,是慢性心衰线粒体功能障碍的重要机制。 展开更多
关键词 慢性心衰 心肌细胞线粒体 钙超载 microRNA 线粒体去乙酰化酶3
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煤层气产量预测分析决策支持系统在上下游一体化项目生产管理中的应用
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作者 李彦忱 刘杰 王箴 《石油科技论坛》 2024年第3期104-111,共8页
通过海量生产数据开展煤层气产量预测是上下游一体化大型项目管理中面临的挑战之一,针对该难题,中国石化集团国际石油勘探开发有限公司海外技术团队研发了煤层气产量预测分析决策支持系统。该系统以SQL、Spotfire、OFM及Enersight等主... 通过海量生产数据开展煤层气产量预测是上下游一体化大型项目管理中面临的挑战之一,针对该难题,中国石化集团国际石油勘探开发有限公司海外技术团队研发了煤层气产量预测分析决策支持系统。该系统以SQL、Spotfire、OFM及Enersight等主要应用软件为底层平台,通过二次开发及整合,搭建了数据整合、数据分析、预测转化及成果应用4个主要模块,以煤层气产量预测复杂性及经常出现的问题为切入点,开展煤层气产量预测综合分析、类比分析及递减分析,实现对产量预测的高效管理。该系统具有方便快捷、固定流程、分工明确、团队协作的特点。通过应用实例,展示了该系统针对海量生产数据,自上而下、由面到点、聚焦关键领域,高效筛查出产量预测的关键问题,并提出可行的修正方案,有效提升了煤层气产量预测精准度,为项目投资决策提供有力支持和保障。 展开更多
关键词 煤层气 产量预测 递减分析 上下游一体化 决策支持
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始新世中期安宁河断裂冲断变形特征及其构造意义:来自断层泥自生伊利石K-Ar定年的证据
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作者 童馗 李智武 +9 位作者 刘树根 I.Tonguç UYSAL 施泽进 李金玺 Andrew TODD 武文慧 王自剑 刘升武 李轲 华天 《地学前缘》 EI CAS CSCD 北大核心 2024年第4期297-313,共17页
青藏高原及其周缘褶皱-冲断带变形方式和时限是验证高原形成众多大陆岩石圈变形动力学端员模型的关键。近年发展起来的断层泥自生伊利石K-Ar定年技术为精确限定褶皱-冲断带变形时限提供了有效手段。鲜水河—安宁河—小江断裂系作为伴随... 青藏高原及其周缘褶皱-冲断带变形方式和时限是验证高原形成众多大陆岩石圈变形动力学端员模型的关键。近年发展起来的断层泥自生伊利石K-Ar定年技术为精确限定褶皱-冲断带变形时限提供了有效手段。鲜水河—安宁河—小江断裂系作为伴随印度-欧亚板块碰撞造山和高原物质侧向挤出过程形成的大型左旋走滑断裂系,其变形过程可为解译印度-欧亚板块碰撞远程应力向东传递方式提供关键证据。本文选取安宁河断裂冕宁—西昌段作为研究对象,在详细构造解析以明确其构造运动学特征的基础上,开展了断层泥自生伊利石K-Ar定年研究,以期精确限定安宁河断裂脆性变形的时间。构造解析表明安宁河断裂在近EW向挤压作用下经历了冲断变形,断层带发育碎斑岩和断层泥,指示为脆性变形。安宁河断裂不同粒级断层泥样品的黏土矿物学和伊利石K-Ar定年分析揭示,随着样品粒级减小,高温2M1型伊利石含量相对低温1M/1Md型伊利石含量逐渐减少,其K-Ar年龄总体呈变年轻趋势,表明不同粒级伊利石K-Ar年龄是由碎屑2M1型和自生1M/1Md型两个多型端员组成的混合年龄。伊利石年龄分析获得自生1M/1Md型伊利石的年龄为(42.6±9.4)Ma,表明安宁河断裂经历了始新世中期的冲断变形。结合前人构造变形、沉积学、低温热年代学和古地磁等研究,我们认为始新世中期青藏高原腹地及其周缘褶皱-冲断带发生准同期的构造挤压变形,其动力学机制可能与印度-欧亚板块硬碰撞以及青藏高原地块的陆内俯冲所导致的先存构造带活化有关。始新世中期安宁河断裂发生冲断变形直接证明印度-欧亚板块碰撞初期的远程应力已传递至青藏高原东南缘地区。 展开更多
关键词 安宁河断裂 断层泥 自生伊利石 K-Ar定年 始新世中期
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泥河湾盆地下马碑遗址2013年发掘简报
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作者 王法岗 杨石霞 +11 位作者 葛俊逸 岳健平 赵克良 Andreu Ollé 李文艳 杨海勇 刘连强 关莹 谢飞 Francesco d’Errico Michael Petraglia 邓成龙 《人类学学报》 CSCD 北大核心 2024年第1期143-156,共14页
下马碑遗址位于广义泥河湾盆地南部的蔚县盆地中东部,是坐落于壶流河二级阶地上的一处旷野遗址。2013年,河北省文物考古研究院对该遗址进行了考古发掘,揭露出丰富的遗物和遗迹现象;2018年起,国内外多家单位共同完成了遗址地层年代、埋... 下马碑遗址位于广义泥河湾盆地南部的蔚县盆地中东部,是坐落于壶流河二级阶地上的一处旷野遗址。2013年,河北省文物考古研究院对该遗址进行了考古发掘,揭露出丰富的遗物和遗迹现象;2018年起,国内外多家单位共同完成了遗址地层年代、埋藏过程、古环境和出土文化遗存的系统性多学科研究工作。该遗址发掘揭露面积12 m^(2),地层剖面深度约为290 cm,自上而下分为7个地层单位,其中第6层为原地埋藏的主文化层,基于光释光与^(14)C测年并经贝叶斯模型计算为距今4.1~3.9万年。本文对下马碑第6层出土的各类遗物与遗迹进行系统报道,主要包括382件石制品、445件动物化石碎片、1件骨器和1套赭石颜料加工遗存,以及1处火塘。该遗址的发现与研究再现了距今4万年前东亚早期现代人加工、使用赭石颜料和复合工具的生活图景,更新了国际学术界对东亚早期现代人行为适应的认识。 展开更多
关键词 泥河湾盆地 下马碑遗址 装柄 赭石 早期现代人
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搜寻第二个地球——系外地球(ET)巡天计划
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作者 葛健 陈雯 +40 位作者 陈永和 宋宗玺 王坚 张辉 李岩 臧伟呈 周丹 张永帅 陈琨 阳应权 毛淑德 黄煦 药新雨 李兴隆 姜海娇 于涌 唐正宏 董峰 高伟 张鸿飞 申超 王峰涛 魏传新 杨宝玉 李豫东 文林 张朋军 张聪聪 谢基伟 马波 邓洪平 刘慧根 段旭亮 王昊宇 黄江江 高扬 王伊菲 王磊 秦根健 刘欣宇 高婕 《空间科学学报》 CAS CSCD 北大核心 2024年第3期400-424,共25页
系外地球科学卫星(ET)将通过采用空间大视场超高精度测光这一关键技术在国际上率先突破生命起源中的系外地球存在及其演化这一重大前沿科学问题. ET卫星将在日地拉格朗日L2点晕(Halo)轨道部署由6台广角凌星望远镜和1台微引力透镜望远镜... 系外地球科学卫星(ET)将通过采用空间大视场超高精度测光这一关键技术在国际上率先突破生命起源中的系外地球存在及其演化这一重大前沿科学问题. ET卫星将在日地拉格朗日L2点晕(Halo)轨道部署由6台广角凌星望远镜和1台微引力透镜望远镜构成的空间天文台,结合凌星法和微引力透镜法,利用空间超大视场和超高精度的光学测光观测,首次发现富有重要意义、被广泛关注的系外地球,并确定其发生率,对目前了解甚少的类地行星和流浪行星进行国际上第一次大规模的种群普查,首次发现流浪地球,并确定其发生率,揭示类地行星和流浪行星起源,为地外生命探寻提供候选者和新方向. ET卫星的观测结果、统计研究以及和对理论的检验将回答系外地球在宇宙中有多普遍,类地行星是如何形成和演化的,流浪行星又是如何起源的这些亟待解决的前沿科学问题.对ET卫星发现的系外地球样本的后随观测,将精确测量其质量、密度和大气成分,有助于深入分析宜居性特征.此外,对ET新发现的大量各种系外行星样本的研究,以及对理论的检验将推动这些种类的行星形成和演化规律的更深入认识, ET的大量高精度、高频次和长基线测光数据将推动星震学、银河系考古学、时域天文学、双星和双星黑洞等领域的研究. 展开更多
关键词 系外行星 类地行星 宜居带 凌星 微引力透镜 测光
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钠离子电池负极材料原位透射电镜研究
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作者 陆佳宁 张智 +1 位作者 高义华 邹进 《电子显微学报》 CAS CSCD 北大核心 2024年第3期371-389,共19页
近年来,由于地球上钠资源分布广泛和丰富,钠离子电池的研究引起了人们的极大兴趣。目前,钠离子电池仍面临着能量密度低、循环稳定性不理想等关键科学问题。钠离子电池存储性能的提高需要对其电极材料储钠微观机制的全面和精确的理解。... 近年来,由于地球上钠资源分布广泛和丰富,钠离子电池的研究引起了人们的极大兴趣。目前,钠离子电池仍面临着能量密度低、循环稳定性不理想等关键科学问题。钠离子电池存储性能的提高需要对其电极材料储钠微观机制的全面和精确的理解。尽管研究者们已经开展了大量的原位透射电子显微学研究来揭示钠离子电池负极材料的储钠特性和微观机制,但是相关的综述鲜见报道。鉴于此,本文综述了近年来原位透射电子显微镜在研究钠离子电池负极材料储钠过程中材料的形貌、微观结构和化学成分等的演化与微观机理的研究进展,阐明了钠离子电池负极材料的组成/结构与钠离子电池电化学性能之间的构效关联。本综述旨在为高效钠离子电池负极材料的高效选择和合理设计提供参考。 展开更多
关键词 钠离子电池 负极材料 原位研究 透射电镜
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New insights on the high-corrosion resistance of UHP Mg-Ge alloys tested in a simulated physiological environment 被引量:1
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作者 Ting Liu Xingrui Chen +4 位作者 Jeffrey Venezuela Yuan Wang Zhiming Shi Wenyi Chen Matthew Dargusch 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1026-1044,共19页
UHP Mg-Ge alloys was recently found to provide excellent corrosion resistance.This paper provides new insights on the mechanism of improved corrosion resistance of UHP Mg-Ge alloys in Hanks’solution.The studied UHP M... UHP Mg-Ge alloys was recently found to provide excellent corrosion resistance.This paper provides new insights on the mechanism of improved corrosion resistance of UHP Mg-Ge alloys in Hanks’solution.The studied UHP Mg-0.5Ge and UHP Mg-1Ge alloys showed superior corrosion resistance compared to UHP Mg and WE43,with the Mg-1Ge exhibiting the best corrosion performance.The exceptional corrosion resistance of the UHP alloy is attributed to(i)Mg_(2)Ge’s ability to suppress cathodic kinetics,(ii)Ge’s capability to accelerate the formation of a highly passive layer,and the(iii)low amounts of corrosion-accelerating impurities. 展开更多
关键词 UHP Mg-Ge alloy Cathodic kinetics suppression Biodegradable metals In vitro corrosion Magnesium corrosion.
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Failure characterization of fully grouted rock bolts under triaxial testing 被引量:1
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作者 Hadi Nourizadeh Ali Mirzaghorbanali +3 位作者 Mehdi Serati Elamin Mutaz Kevin McDougall Naj Aziz 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期778-789,共12页
Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic st... Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic stress conditions.Under these conditions,it is assumed that the intermediate principal stress(σ_(2))equals the minimum principal stress(σ_(3)).This assumption overlooks the potential variations in magnitudes of in situ stress conditions along all three directions near an underground opening where a rock bolt is installed.In this study,a series of push tests was meticulously conducted under triaxial conditions.These tests involved applying non-uniform confining stresses(σ_(2)≠σ_(3))to cubic specimens,aiming to unveil the previously overlooked influence of intermediate principal stresses on the strength properties of rock bolts.The results show that as the confining stresses increase from zero to higher levels,the pre-failure behavior changes from linear to nonlinear forms,resulting in an increase in initial stiffness from 2.08 kN/mm to 32.51 kN/mm.The load-displacement curves further illuminate distinct post-failure behavior at elevated levels of confining stresses,characterized by enhanced stiffness.Notably,the peak load capacity ranged from 27.9 kN to 46.5 kN as confining stresses advanced from σ_(2)=σ_(3)=0 to σ_(2)=20 MPa and σ_(3)=10 MPa.Additionally,the outcomes highlight an influence of confining stress on the lateral deformation of samples.Lower levels of confinement prompt overall dilation in lateral deformation,while higher confinements maintain a state of shrinkage.Furthermore,diverse failure modes have been identified,intricately tied to the arrangement of confining stresses.Lower confinements tend to induce a splitting mode of failure,whereas higher loads bring about a shift towards a pure interfacial shear-off and shear-crushed failure mechanism. 展开更多
关键词 Rock bolts Bolt-grout interface Bond strength Push test Triaxial tests
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城市湿地的小气候调节功能及其空间梯度效应
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作者 刘洛甫 张伟 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期133-142,共10页
在全球气候变化、快速城市化等多重因素的共同作用下,城市热环境日益恶化,严重威胁着城市居民的健康.通过对杭州市西溪湿地的多季节实地观测,分析和量化了西溪湿地的局地小气候调节功能,探讨了其空间梯度效应,剖析了其关键影响因素.研... 在全球气候变化、快速城市化等多重因素的共同作用下,城市热环境日益恶化,严重威胁着城市居民的健康.通过对杭州市西溪湿地的多季节实地观测,分析和量化了西溪湿地的局地小气候调节功能,探讨了其空间梯度效应,剖析了其关键影响因素.研究结果表明:①西溪湿地具有显著的局地小气候调节功能.其在温度、湿度和风速等方面调节效应的平均影响范围分别为137.5,150.0,87.5 m.此外,西溪湿地的局地小气候调节功能还表现出显著的空间梯度效应.②城市湿地的温度调节效应和人体舒适度调节效应具有显著的季节差异.在人体舒适度较低的夏季和冬季,西溪湿地局地小气候调节效应的范围和幅度均大于人体舒适度更高的春季和秋季.季节性湿地的建设有助于最有效地发挥城市湿地的局地小气候调节功能.③太阳辐射和湿度是影响西溪湿地局地小气候调节功能的关键气象因子,它们显著影响着西溪湿地的冷岛效应、湿岛效应和人体舒适度提升效应.在未来的城市湿地规划和建设过程中,将湿地布局在具有特定气象条件的区域,能够更好地发挥城市湿地的局地小气候调节功能. 展开更多
关键词 城市湿地 小气候效应 空间梯度效应 影响因素 杭州
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Spatial analysis of the osteoarthritis microenvironment: techniques, insights, and applications 被引量:1
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作者 Xiwei Fan Antonia Rujia Sun +5 位作者 Reuben S.E.Young Isaac O.Afara Brett R.Hamilton Louis Jun Ye Ong Ross Crawford Indira Prasadam 《Bone Research》 SCIE CAS CSCD 2024年第1期1-19,共19页
Osteoarthritis(OA)is a debilitating degenerative disease affecting multiple joint tissues,including cartilage,bone,synovium,and adipose tissues.OA presents diverse clinical phenotypes and distinct molecular endotypes,... Osteoarthritis(OA)is a debilitating degenerative disease affecting multiple joint tissues,including cartilage,bone,synovium,and adipose tissues.OA presents diverse clinical phenotypes and distinct molecular endotypes,including inflammatory,metabolic,mechanical,genetic,and synovial variants.Consequently,innovative technologies are needed to support the development of effective diagnostic and precision therapeutic approaches.Traditional analysis of bulk OA tissue extracts has limitations due to technical constraints,causing challenges in the differentiation between various physiological and pathological phenotypes in joint tissues.This issue has led to standardization difficulties and hindered the success of clinical trials.Gaining insights into the spatial variations of the cellular and molecular structures in OA tissues,encompassing DNA,RNA,metabolites,and proteins,as well as their chemical properties,elemental composition,and mechanical attributes,can contribute to a more comprehensive understanding of the disease subtypes.Spatially resolved biology enables biologists to investigate cells within the context of their tissue microenvironment,providing a more holistic view of cellular function.Recent advances in innovative spatial biology techniques now allow intact tissue sections to be examined using various-omics lenses,such as genomics,transcriptomics,proteomics,and metabolomics,with spatial data.This fusion of approaches provides researchers with critical insights into the molecular composition and functions of the cells and tissues at precise spatial coordinates.Furthermore,advanced imaging techniques,including high-resolution microscopy,hyperspectral imaging,and mass spectrometry imaging,enable the visualization and analysis of the spatial distribution of biomolecules,cells,and tissues.Linking these molecular imaging outputs to conventional tissue histology can facilitate a more comprehensive characterization of disease phenotypes.This review summarizes the recent advancements in the molecular imaging modalities and methodologies for in-depth spatial analysis.It explores their applications,challenges,and potential opportunities in the field of OA.Additionally,this review provides a perspective on the potential research directions for these contemporary approaches that can meet the requirements of clinical diagnoses and the establishment of therapeutic targets for OA. 展开更多
关键词 INSIGHT SPATIAL enable
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Nuance of inward rectifying potassium(Kir)channel dysfunctions in neurodegenerative diseases 被引量:1
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作者 Benjamin Garland Linlin Ma 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1195-1196,共2页
Neurodegenerative disorders are highly prevalent and diverse in nature.Their manifestation largely depends on the cell types involved,with aberrant inflammatory episodes progressively inducing a constellation of pheno... Neurodegenerative disorders are highly prevalent and diverse in nature.Their manifestation largely depends on the cell types involved,with aberrant inflammatory episodes progressively inducing a constellation of phenotypes that are classified into specific diseases based on their neuropathological traits.The two most prevalent neurodegenerative diseases worldwide,Alzheimer’s disease(AD)and Parkinson’s disease(PD),for example,share notable similarities,yet they differ in terms of the specific cell types lost within the central nervous system(CNS).The significant and progressive loss of cortical and certain subcortical neurons in various regions is a major defining trait of AD.In contrast,the specific loss of dopaminergic neurons(DA)within the substantial nigra pars compacta(SNpc)is sufficient to cause motor symptoms associated with PD.Another devastating condition arising from neurodegeneration within the CNS,amyotrophic lateral sclerosis(ALS),results in the progressive death of upper and lower motor neurons.This degeneration originates in oligodendrocytes,whose defective myelination abilities lead to the denervation of the anterior horn,aggravating motor neuron death. 展开更多
关键词 diseases DEGENERATIVE DEGENERATION
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Towards advanced zinc anodes by interfacial modification strategies for efficient aqueous zinc metal batteries 被引量:1
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作者 Changchun Fan Weijia Meng Jiaye Ye 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期79-110,I0003,共33页
Developing sustainable and clean energy sources(e.g.,solar,wind,and tide energy)is essential to achieve the goal of carbon neutrality.Due to the discontinuous and inco nsistent nature of common clean energy sources,hi... Developing sustainable and clean energy sources(e.g.,solar,wind,and tide energy)is essential to achieve the goal of carbon neutrality.Due to the discontinuous and inco nsistent nature of common clean energy sources,high-performance energy storage technologies are a critical part of achieving this target.Aqueous zinc metal batteries(AZMBs)with inherent safety,low cost,and competitive performance are regarded as one of the promising candidates for grid-scale energy storage.However,zinc metal anodes(ZMAs)with irreversible problems of dendrite growth,hydrogen evolution reaction,self-corrosio n,and other side reactions have seriously hindered the development and commercialization of AZMBs.An increasing number of researchers are focusing on the stability of ZMAs,so assessing the effectiveness of existing research strategies is critical to the development of AZMBs.This review aims to provide a comprehensive overview of the fundamentals and challenges of AZMBs.Resea rch strategies for interfacial modification of ZMAs are systematically presented.The features of artificial interfacial coating and in-situ interfacial coating of ZMAs are compared and discussed in detail,as well as the effect of modified interfacial ZMA on the full-battery performance.Finally,perspectives are provided on the problems and challenges of ZMAs.This review is expected to offer a constructive reference for the further development and commercialization of AZMBs. 展开更多
关键词 Aqueous zinc metal batteries Zinc metal anode Interfacial modification Artificial interfacial coating In-situ interfacial coating
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Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older 被引量:6
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作者 Erik A.Willis Stephen D.Herrmann +8 位作者 Mary Hastert Chelsea L.Kracht Tiago V.Barreira John M.Schuna Jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy J.Brown Barbara E.Ainsworth 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期13-17,F0003,共6页
Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values ... Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,Embase,SPORTDiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older adults.MET values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MET_(60+))to account for the lower resting metabolic rate in older adults.Results:We identified 68 articles and extracted energy expenditure data on 427 PAs.From these,we derived 99 unique Specific Activity codes with corresponding MET_(60+)values for older adults.We developed a website to present the OA Compendium MET_(60+)values:https://pacompendium.com.Conclusion:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older adults.It is an accessible resource that will allow researchers,educators,and practitioners to find MET_(60+)values for older adults for use in PA research and practice. 展开更多
关键词 Energy expenditure EXERCISE MET Older adults
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“双碳”目标下辽宁省低碳乡村建设的路径研究
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作者 刘桢 郑帅 《农业经济》 北大核心 2024年第1期79-81,共3页
在“双碳”战略背景下,低碳建设已成为乡村发展的现实要求,是实现乡村高质量发展的重要途径之一。然而,辽宁省低碳乡村建设中仍面临用能结构传统、住宅节能标准低、人居环境质量差、低碳意识薄弱、低碳农业和碳汇经济体系不完善等现实... 在“双碳”战略背景下,低碳建设已成为乡村发展的现实要求,是实现乡村高质量发展的重要途径之一。然而,辽宁省低碳乡村建设中仍面临用能结构传统、住宅节能标准低、人居环境质量差、低碳意识薄弱、低碳农业和碳汇经济体系不完善等现实困境。由此,本文着眼于乡村能源供给、节能改造、环境整治、村民意识、保障机制五个方面,提出适合我省低碳乡村建设的路径与策略。 展开更多
关键词 辽宁省 双碳 低碳建设 乡村建设
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Suppressive effects of exercise-conditioned serum on cancer cells:A narrative review of the influence of exercise mode,volume,and intensity 被引量:1
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作者 Francesco Bettariga Dennis R.Taaffe +3 位作者 Daniel A.Galvao Chris Bishop Jin-Soo Kim Robert U.Newton 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期484-498,F0003,共16页
Cancer is a major cause of morbidity and mortality worldwide,and the incidence is increasing,highlighting the need for effective strategies to treat this disease.Exercise has emerged as fundamental therapeutic medicin... Cancer is a major cause of morbidity and mortality worldwide,and the incidence is increasing,highlighting the need for effective strategies to treat this disease.Exercise has emerged as fundamental therapeutic medicine in the management of cancer,associated with a lower risk of recur-rence and increased survival.Several avenues of research demonstrate reduction in growth,proliferation,and increased apoptosis of cancer cells,including breast,prostate,colorectal,and lung cancer,when cultured by serum collected after exercise in vitro(i.e.,the cultivation of cancer cell lines in an experimental setting,which simplifies the biological system and provides mechanistic insight into cell responses).The underlying mechanisms of exercise-induced cancer suppressive effects may be attributed to the alteration in circulating factors,such as skeletal muscle-induced cytokines(i.e.,myokines)and hormones.However,exercise-induced tumor suppressive effects and detailed information about training interventions are not well investigated,constraining more precise application of exercise medicine within clinical oncology.To date,it remains unclear what role different training modes(i.e.,resistance and aerobic training)as well as volume and intensity have on exercise-condi-tioned serum and its effects on cancer cells.Nevertheless,the available evidence is that a single bout of aerobic training at moderate to vigorous intensity has cancer suppressive effects,while for chronic training interventions,exercise volume appears to be an influential candidate driving cancer inhibitory effects regardless of training mode.Insights for future research investigating training modes,volume and intensity are provided to further our understanding of the effects of exercise-conditioned serum on cancer cells. 展开更多
关键词 Cancer cells High intensity interval training Moderate intensity continuous training Resistance training MYOKINES
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泵机一体化的轴流式血泵模拟优化
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作者 何翊诚 邱胤轩 +2 位作者 张亚 崔佳鑫 鄂殿玉 《中国医学物理学杂志》 CSCD 2024年第9期1152-1162,共11页
针对现有的轴流式血泵存在一定的结构缺陷,导致性能不足和血液相容性差等问题,提出以一种泵机一体化的轴流式血泵为研究对象,利用计算流体力学方法,对其几何结构进行优化改进。同时研究不同运行参数对该血泵性能的影响,并与实验的数据... 针对现有的轴流式血泵存在一定的结构缺陷,导致性能不足和血液相容性差等问题,提出以一种泵机一体化的轴流式血泵为研究对象,利用计算流体力学方法,对其几何结构进行优化改进。同时研究不同运行参数对该血泵性能的影响,并与实验的数据进行比较,确定最佳的运行参数。本研究对该血泵的流场特性进行全面的分析,进一步揭示其内部的流动规律,并采用DPM方法模拟血液中红细胞的流动行为及其受剪切应力的情况,完成对该血泵的血液相容性的评估。研究表明,新型的血泵在扬程方面表现出良好的性能。在转速为9000r/min、流量为6.24L/min的最佳工况下,血泵的扬程比原结构提升16%,效率达到25%,能够满足大部分人的生理需求。此外血泵内大部分区域的压力梯度和速度梯度都比较均匀,内部流场情况比较稳定,能够有效避免溶血现象的发生。本研究优化改进的血泵能在确保高性能和良好的流场特性的同时具备较好的血液相容性,可为轴流式血泵的结构优化和改进提供重要的参考依据。 展开更多
关键词 轴流式血泵 泵机一体化 结构优化 流场特性 血液相容性
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BMPRⅡ^(+)neural precursor cells isolated and characterized from organotypic neurospheres:an in vitro model of human fetal spinal cord development 被引量:1
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作者 Michael W.Weible II Michael D.Lovelace +2 位作者 Hamish D.Mundell Tsz Wai Rosita Pang Tailoi Chan-Ling 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期447-457,共11页
Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not... Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well understood.Type-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is absent.Immunofluorescence was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory columns.Parenchymal and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,CD34/CD39.LIF immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/CD118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,cytoarchitecture.These neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent precursors.Dissociated cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage cells.Fluorescence-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in culture.This is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal cords.Our data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterized by surface BMPRⅡ^(+)hNPCs.Our study has provided a new methodology for an in vitro model capable of amplifying human fetal spinal cord cell numbers for>10 passages.Investigations of the role BMPRⅡplays in spinal cord development have primarily relied upon mouse and rat models,with interpolations to human development being derived through inference.Because of significant species differences between murine biology and human,including anatomical dissimilarities in central nervous system(CNS)structure,the findings made in murine models cannot be presumed to apply to human spinal cord development.For these reasons,our human in vitro model offers a novel tool to better understand neurodevelopmental pathways,including BMP signaling,as well as spinal cord injury research and testing drug therapies. 展开更多
关键词 BMPRⅡ bone morphogenetic protein histotypic human spinal cord development leukemia inhibitory factor NEUROSPHERE ORGANOTYPIC reaggregate sensory columns
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Gradient coil design with enhanced shielding constraint for a cryogen-free superconducting MRI system 被引量:1
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作者 Yaohui Wang Weimin Wang +3 位作者 Hui Liu Shunzhong Chen Feng Liu Qiuliang Wang 《Magnetic Resonance Letters》 2024年第1期1-9,共9页
The relatively fragile low-temperature stability of cryogen-free superconducting magnetic resonance imaging(MRI)magnets requires the careful management of exogenous heat sources.A strongly shielded gradient magnetic f... The relatively fragile low-temperature stability of cryogen-free superconducting magnetic resonance imaging(MRI)magnets requires the careful management of exogenous heat sources.A strongly shielded gradient magnetic field is important for the optimal operation of cryogen-free MRI systems.In this study,we present an enhanced shielding method incorporating a regionalized stray field constraining strategy.By optimizing the constraint parameters,we could develop engineering-feasible gradient coil schemes without increasing system complexity but with the stray field intensity reduced by half.In real measurement in an integrated MRI system,the developed gradient assembly demonstrated good performance and supported to output images of excellent quality.Our findings suggested that the proposed method could potentially form a useful design paradigm for cryogen-free MRI magnets. 展开更多
关键词 MRI Gradient coil Superconducting magnet Cryogen-free Magnetic shielding
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Determining rock crack stress thresholds using ultrasonic through-transmission measurements
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作者 Jiangwan He Mehdi Serati +1 位作者 Martin Veidt Arthur De Alwis 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期67-80,共14页
The crack initiation stress threshold is widely used in excavation industries as rock spalling strength when designing deep underground structures to avoid unwanted brittle failures.While various strain-based methods ... The crack initiation stress threshold is widely used in excavation industries as rock spalling strength when designing deep underground structures to avoid unwanted brittle failures.While various strain-based methods have been developed for the estimation of this critical design parameter,such methods are destructive and often requires subjective interpretations of the stress–strain curves,particularly in rocks with pre-existing microcracks or high porosity.This study explore the applicability of non-destructive ultrasonic through-transmission methods for determining rock damage levels by assessing the changes in transmitted signal characteristics during loading.The change in velocity,amplitude,dominant frequency,and root-mean-square voltage are investigated with four different rock types including marble,sandstone,granite,and basalt under various stress levels.Results suggest the rate of signal variations can be reliably used to estimate crack closure and crack initiation stress levels across the tested rocks before failure.Comparison of the results between the conventional techniques and the new proposed methods based on ultrasonic monitoring are further discussed. 展开更多
关键词 ULTRASONIC Non-destructive testing Brittle rock Crack initiation VELOCITY AMPLITUDE FREQUENCY
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The risk of prostate cancer on incidental finding of an avid prostate uptake on 2-deoxy-2-[^(18)F]fluoro-D-glucose positron emission tomography/computed tomography for non-prostate cancer-related pathology:A single centre retrospective study
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作者 Anthony Franklin Troy Gianduzzo +7 位作者 Boon Kua David Wong Louise McEwan James Walters Rachel Esler Matthew J.Roberts Geoff Coughlina John W.Yaxley 《Asian Journal of Urology》 CSCD 2024年第1期33-41,共9页
Objective:To review the risk of prostate cancer(PCa)in men with incidentally reported increased intraprostatic uptake at 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography(18F-FDG PET/CT)... Objective:To review the risk of prostate cancer(PCa)in men with incidentally reported increased intraprostatic uptake at 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography(18F-FDG PET/CT)ordered at Department of Urology,The Wesley Hospital,Brisbane,QLD,Australia for non-PCa related pathology.Methods:Retrospective analysis of consecutive men between August 2014 and August 2019 presenting to a single institution for 18F-FDG PET/CT for non-prostate related conditions was conducted.Men were classified as benign,indeterminate,or malignant depending of the results of prostate-specific antigen(PSA),PSA velocity,biopsy histopathology,and three-Tesla(3 T)multiparametric MRI(mpMRI)Prostate Imaging Reporting and Data System score,or gallium-68-prostate-specific membrane antigen(68Ga-PSMA)PET/CT results.Results:Three percent(273/9122)of men demonstrated 18F-FDG avidity within the prostate.Eighty-five percent(231/273)were further investigated,including with PSA tests(227/231,98.3%),3 T mpMRI(68/231,29.4%),68Ga-PSMA PET/CT(33/231,14.3%),and prostate biopsy(57/231,24.7%).Results were considered benign in 130/231(56.3%),indeterminate in 31/231(13.4%),and malignant in 70/231(30.3%).PCa was identified in 51/57(89.5%)of the men who proceeded to biopsy,including 26/27(96.3%)men with Prostate Imaging Reporting and Data System scores 4-5 mpMRI and six men with a positive 68Ga-PSMA PET/CT.The most common Gleason score on biopsy was greater than or equal to 4+5(14/51,27.5%).68Ga-PSMA PET/CT was concordant with the 18F-FDG findings in 26/33(78.8%).All 13 men with a positive concordant 18F-FDG,3 T mpMRI,and 68Ga-PSMA PET/CT had PCa on biopsy.There was no statistically significant difference in the 18F-FDG maximum standardized uptake value between the benign or malignant groups(5.7 vs.6.1;p=0.580).Conclusion:In this study,after an incidental finding of an avid intraprostatic lesion on 18F-FDG PET/CT,70 of the 231 cases(30.3%;0.8%of the entire cohort)had results consistent with PCa,most commonly as Gleason score greater than or equal to 4+5 disease.Unless there is limited life expectancy due to competing medical co-morbidity,men with an incidental finding of intraprostatic uptake on 18F-FDG should be further investigated using principles of PCa detection. 展开更多
关键词 Prostatecancer Positionemission tomography Multiparametric magneticresonance imaging Prostatebiopsy
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