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An ultrathin wide-band planar metamaterial absorber based on a fractal frequency selective surface and resistive film

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Chinese Physics B 2013年第6期22卷 570-575页

作者：范跃农程用志聂彦王鲜龚荣洲 School of Optical and Electronic Information Huazhong University of Science and Technology Department of Mechanical and Electronic Engineering Jingdezhen Ceramic Institute

We propose an ultrathin wide-band metamaterial absorber （MA） based on a Minkowski （MIK） fractal frequency selective surface and resistive film. This absorber consists of a periodic arrangement of dielectric substrates sandwiched with an MIK fractal loop structure electric resonator and a resistive film. The finite element method is used to simulate and analyze the absorption of the MA. Compared with the MA-backed copper film, the designed MA-backed resistive film exhibits an absorption of 90% at a frequency region of 2 GHz-20 GHz. The power loss density distribution of the MA is further illustrated to explain the mechanism of the proposed MA. Simulated absorptions at different incidence cases indicate that this absorber is polarization-insensitive and wide-angled. Finally, further simulated results indicate that the surface resistance of the resistive film and the dielectric constant of the substrate can affect the absorbing property of the MA. This absorber may be used in many military fields.

关键词： wide-band metamaterial absorber fractal frequency selective surface resistive films

“互联网+”视阈下国内外学习焦虑元分析及对策研究

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数字教育 2016年第5期2卷 7-11页

作者：智飞飞乜勇陕西师范大学教育学院陕西西安710062

现代信息技术的迅猛发展将人类带入了"互联网+"时代,在此时代背景下的网络学习因此而不断进行着分解与重构,此过程中的学习问题也变得越来越突出。笔者以2004年到2015年为研究年限,综合考虑国内与国外有关网络环境下的学习焦虑的研究,... 详细信息

现代信息技术的迅猛发展将人类带入了"互联网+"时代,在此时代背景下的网络学习因此而不断进行着分解与重构,此过程中的学习问题也变得越来越突出。笔者以2004年到2015年为研究年限,综合考虑国内与国外有关网络环境下的学习焦虑的研究,以元分析法对12年的文章进行整体综述,以文献数量、研究内容、研究方法、发文时间四个维度进行综述,通过对比国内外有关网络学习焦虑研究的不同,发现我国有关网络学习焦虑研究的问题并提出改进策略。

关键词： “互联网+” 学习焦虑元分析

教育传播视域下微课的传播特征分析及优化策略研究——基于第二届全国高校微课教学比赛获奖作品的分析

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中国医学教育技术 2017年第3期31卷 279-282页

作者：智飞飞乜勇陕西师范大学教育学院西安710062

2007年以来,随着翻转课堂在我国的盛行,教育界对其核心要素—微课的研究与实践呈现井喷式发展,但研究内容中甚少涉及从教育传播学的角度分析微课的传播特征。文章从教育者、教育信息、教育媒体、教育环境四个维度对第二届全国高校微课... 详细信息

2007年以来,随着翻转课堂在我国的盛行,教育界对其核心要素—微课的研究与实践呈现井喷式发展,但研究内容中甚少涉及从教育传播学的角度分析微课的传播特征。文章从教育者、教育信息、教育媒体、教育环境四个维度对第二届全国高校微课教学比赛获奖作品进行逐个分析,发现国内微课教学交互不足、媒体呈现较单一、教学创新与深度有待提高、微课之"微引入"需着重设计等问题,以期为后续的微课设计与制作提供借鉴。

关键词：微课教育传播微课教学优化策略

Advances in therapies using mesenchymal stem cells and their exosomes for treatment of peripheral nerve injury:state of the art and future perspectives

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Neural Regeneration Research 2025年第11期20卷 3151-3171页

作者： Fatima Aldali Chunchu Deng Mingbo nie Hong Chen Department of Rehabilitation Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Orthopedics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

“Peripheral nerve injury”refers to damage or trauma affecting nerves outside the brain and spinal *** nerve injury results in movements or sensation impairments,and represents a serious public health *** severed peripheral nerves have been effectively joined and various therapies have been offered,recovery of sensory or motor functions remains limited,and efficacious therapies for complete repair of a nerve injury remain *** emerging field of mesenchymal stem cells and their exosome-based therapies hold promise for enhancing nerve regeneration and *** stem cells,as large living cells responsive to the environment,secrete various factors and *** latter are nano-sized extracellular vesicles containing bioactive molecules such as proteins,microRNA,and messenger RNA derived from parent mesenchymal stem *** have pivotal roles in cell-to-cell communication and nervous tissue function,offering solutions to changes associated with cell-based *** ongoing investigations,mesenchymal stem cells and mesenchymal stem cell-derived exosome-based therapies are in the exploratory stage.A comprehensive review of the latest preclinical experiments and clinical trials is essential for deep understanding of therapeutic strategies and for facilitating clinical *** review initially explores current investigations of mesenchymal stem cells and mesenchymal stem cell-derived exosomes in peripheral nerve injury,exploring the underlying ***,it provides an overview of the current status of mesenchymal stem cell and exosomebased therapies in clinical trials,followed by a comparative analysis of therapies utilizing mesenchymal stem cells and ***,the review addresses the limitations and challenges associated with use of mesenchymal stem cell-derived exosomes,offering potential solutions and guiding future directions.

关键词： clinical trials exosome extracellular vesicles mesenchymal stem cells nerve regeneration peripheral nerve injury pre-clinical experiments

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2025年第2期20卷 503-517页

作者： Qi Liu Jianye Xie Runxue Zhou Jin Deng Weihong nie Shuwei Sun Haiping Wang Chunying Shi Department of Human Anatomy Histology and EmbryologySchool of Basic MedicineQingdao UniversityQingdaoShandong ProvinceChina Department of Neurology The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina Department of General Practice The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic ***,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in ***,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic *** metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ***,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel ***-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in *** results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor *** findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

关键词： angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 neuroprotection self-assembling nanofiber hydrogel

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 246-257页

作者： ZHANG Jian nie Wei HUANG Jin ZHU Ke LIU Ruxia ZHANG Ruizhi LUO Guoqiang SHEN Qiang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons

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Neural Regeneration Research 2025年第1期20卷 209-223页

作者： Shi-Yan Sun Lingyun nie Jing Zhang Xue Fang Hongmei Luo Chuanhai Fu zhiyi Wei Ai-Hui Tang Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Brain Function and DiseaseMinistry of Education Key Laboratory for Membrane-less Organelles and Cellular DynamicsDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina CAS Center for Excellence in Molecular Cell Sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Neurobiology School of Life SciencesSouthern University of Science and TechnologyShenzhenGuangdong ProvinceChina Brain Research Center Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina

Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and ***-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains *** this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative ***,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic *** of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and *** down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive *** together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.

关键词： actin cytoskeleton dendrite KANK1 KIF21A microtubule spine morphology spine synaptic plasticity talin1

国家与社会之间——论社会中介组织对中国社会转型的影响

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天津行政学院学报 2002年第2期4卷 16-21页

作者：唐兴霖吴志军聂勇浩中山大学政治学与行政学系广州510275

中国市场经济的发展和公民社会的兴起,社会中介组织的发展是一个必然的选择。社会中介组织是政府和私营部门之外的“第三种力量”,他可以协调个人和政府之间的关系;而当前中国社会中介组织的发展却面临独立性差、功能不全、总量不足、... 详细信息

中国市场经济的发展和公民社会的兴起,社会中介组织的发展是一个必然的选择。社会中介组织是政府和私营部门之外的“第三种力量”,他可以协调个人和政府之间的关系;而当前中国社会中介组织的发展却面临独立性差、功能不全、总量不足、体制混乱等问题,因而规范政府与社会中介组织的关系,促进中介组织的发展则是当务之急。

关键词：公民社会社会中介组织社会转型

InNi alloy-induced interface effect promoting the parallel electron transfer: improved photothermal catalytic CO2 hydrogenation

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Science China Chemistry 2025年

作者： Haoyu Zhang Yuhang Li Yu nie Xinyu Dou Haodong Ji Xin Tan Jinhua Ye Tao Yu School of Chemical Engineering and Technology Tianjin University Eco-environment and Resource Efficiency Research Laboratory School of Environment and Energy Peking University Shenzhen Graduate School School of Environmental Science and Engineering Tianjin University Advanced Catalytic Materials Research Center School of Materials Science and Engineering Tianjin University Research Center for Solar Driven Carbon Neutrality Hebei University

Photothermal catalytic CO2hydrogenation is an effective means of utilizing carbon ***,it is severely limited in terms of kinetics and ***,it is necessary to meticulously design catalysts to solve this ***,a sandwich structured NiO@InNi/In2O3is designed to intrinsically regulate the direction of photogenerated carriers transfer,resulting in a CO yield of 42.97 mmol g-1h-1(1290.3μmol h-1) with a selectivity near to 100%.InNi alloy favors the collection of photogenerated carriers by the parallel way and enhancement of the adsorption and activation of *** grown on the surface of InNi alloy not only improves the adsorption of H2and provides sufficient H+for the reaction,but also makes InNi alloy more stable during the reaction *** photothermal effect caused by In2O3accelerates the transfer of photogenerated carriers and increases the surface temperature of the catalyst,thereby synergistically promoting the reaction from a kinetic *** work ameliorates the kinetic and thermodynamic limitations of the photothermal catalytic CO2hydrogenation process through rationally designing the electron transfer direction of the sandwich structured catalysts to parallel way.

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