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Between the City and Images:An Analysis of Mainstream Media’s Paths of Constructing the Cultural Memory of a City:Taking Chengdu Radio and Television’s“Hi Chengdu”as an Example 被引量:1
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作者 Ding Ran Shi Lei 《Contemporary Social Sciences》 2024年第2期97-111,共15页
Mainstream media play a crucial role in constructing the cultural memory of a city.This study used 319 short videos released by“Hi Chengdu,”a new media product of Chengdu Radio and Television,as samples.Based on the... Mainstream media play a crucial role in constructing the cultural memory of a city.This study used 319 short videos released by“Hi Chengdu,”a new media product of Chengdu Radio and Television,as samples.Based on the grounded theory,a research framework encompassing“content,technology,and discourse”was established to explore the paths through which mainstream media construct the cultural memory.Regarding content,this paper emphasized temporal and spatial contexts and urban spaces,delving deep into the themes of the cultural memory and vehicles for it.In terms of technology,this paper discussed the practice of leveraging audio/visual-mode discourse to stitch together the impressions of a city and evoke emotional resonance to create a“flow”of memory.As for discourse,this paper looked at the performance of a communication ritual to frame concepts and shape urban identity.It is essential to break free from conventional thinking and leverage local culture as the primary driving force to further boost a city’s productivity,in order to excel in cultural communication. 展开更多
关键词 the cultural memory of a city short videos the grounded theory Chengdu Radio and television “Hi Chengdu”
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An Investigation of Lighting Levels and Sleep Quality
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作者 Kathy Sexton-Radek Amina Mira 《Health》 2024年第9期794-800,共7页
Sleep quality in young adults is compromised. Instead of the recommended 7 hours, young adults’ schedule interruptions disturb sleep to a typical six and a half hours, with common disturbances in falling asleep and s... Sleep quality in young adults is compromised. Instead of the recommended 7 hours, young adults’ schedule interruptions disturb sleep to a typical six and a half hours, with common disturbances in falling asleep and staying asleep. Recent literature has identified an association between academic performance, negative mood state and low activity level in young adults with sleep disturbances. Young adulthood is a time for the installation of sleep health. Both individual and schedule impositions to the young adults’ sleep schedule are to be modified to obtain Sleep Health. Recent research has identified daytime light effects on sleep such as blue light from electronics as alerting and low level light for relaxation. The aim of this study was to identify sleep quality effects with varying light exposures. It was hypothesized that bright (>450 lux) light conditions would be considered focusing and low light (<220 lux) would be considered calming. We hypothesized that sleep quality would improve by 5% with the introduction of a calm light condition. Undergraduates from a small midwestern university were invited to participate in the study in exchange for a gift card. Six participants completed the study, two males, four females all between 21 - 24 years old. Both hypotheses were supported by qualitative analysis. 展开更多
关键词 LIGHT Sleep Quality lighting Sleep Disturbance
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Application of Intelligent Technology in Building Electrical Lighting Project
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作者 Yingling Dai Qinghua Zhao 《Journal of Electronic Research and Application》 2024年第3期112-117,共6页
The rapid development of intelligent technology has led to its introduction into the field of electrical lighting in buildings.It provides more technical support for system design,use,and management,and creates a comf... The rapid development of intelligent technology has led to its introduction into the field of electrical lighting in buildings.It provides more technical support for system design,use,and management,and creates a comfortable and safe living environment.The adoption of intelligent technology enables the creation of an intelligent management system,where controllers and sensors are used to adjust the light source within the building,monitor and manage the lighting system in real time,monitor the energy consumption and safety of the system,and achieve the goal of energy saving and emission reduction.This paper briefly discusses the application and significance of intelligent technology in electrical lighting and puts forward design ideas to optimize electrical lighting and measures for lighting system management. 展开更多
关键词 Intelligent technology BUILDINGS Electric lighting
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Construction and Development of the National Experimental Teaching Demonstration Center for Drama and Film and Television Disciplines
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作者 Wei Zhou 《Journal of Contemporary Educational Research》 2024年第9期271-276,共6页
Taking the National Experimental Teaching Demonstration Center of the Central Academy of Drama as an example,this article explores the construction and development of the National Experimental Teaching Demonstration C... Taking the National Experimental Teaching Demonstration Center of the Central Academy of Drama as an example,this article explores the construction and development of the National Experimental Teaching Demonstration Center for the practical teaching of drama and film and television disciplines.The article first introduces the background and importance of the demonstration center and then analyzes in depth the construction content and achievements of the demonstration center from four aspects:practical teaching philosophy,practical teaching system,practical teaching resources,and practical teaching effects.Finally,the article summarizes the experience and shortcomings of the demonstration center and proposes future development directions and suggestions. 展开更多
关键词 Drama and film and television disciplines Practical teaching National Experimental Teaching Demonstration Center Central Academy of Drama
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The Application of Intelligent Lighting in Thermal Power Plants
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作者 Xiaozhong Kang Shuangqiang Liu +1 位作者 Guoqing Hu Haibin Huang 《Journal of Electronic Research and Application》 2024年第4期180-185,共6页
With the rapid development of electronic information technology,the Internet of Things(IoT),Internet technology,and modern communication technology,people are demanding higher standards for the building environment.Es... With the rapid development of electronic information technology,the Internet of Things(IoT),Internet technology,and modern communication technology,people are demanding higher standards for the building environment.Especially in modern large-scale buildings with high levels of industrialization,lighting systems should also be optimized accordingly.This article explores the application path of intelligent lighting in thermal power plants for reference. 展开更多
关键词 Intelligent lighting Thermal power plants Application path
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Application of Smart Streetlights in Urban Road Lighting
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作者 Huiyan Yang 《Journal of Electronic Research and Application》 2024年第3期83-88,共6页
The construction and installation of street lighting is an important element in the modernization of China’s cities.Besides,it also plays an important role in raising the living standards of the people.In recent year... The construction and installation of street lighting is an important element in the modernization of China’s cities.Besides,it also plays an important role in raising the living standards of the people.In recent years,with the technological and economic development,smart street lighting has gradually emerged.Key functions of smart street lighting include road illumination,cultural promotion,meteorological monitoring,public broadcasting,and 5G micro-base stations.The overall quality of smart street lighting construction directly impacts the effectiveness of urban development and the city’s comprehensive growth.This paper analyzes the concept of smart street lighting,its advantages and disadvantages,the functionalities of smart street light systems,and the application of smart street lighting in urban road illumination. 展开更多
关键词 Smart streetlights Urban street lighting LED streetlights
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Application of Landscape Smart Lighting in Construction Projects
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作者 Yingling Dai Qinghua Zhao 《Journal of World Architecture》 2024年第2期78-83,共6页
Currently,to effectively construct high-quality smart cities and achieve comprehensive governance goals,various industries must embrace the transformation and upgrading of traditional management methods through the in... Currently,to effectively construct high-quality smart cities and achieve comprehensive governance goals,various industries must embrace the transformation and upgrading of traditional management methods through the integration of new technologies.Among these,landscape smart lighting serves as a crucial tool for advancing smart city development.By judiciously applying this technology,it is possible to enhance traditional lighting methods and offer people novel experiences in their daily lives.Recognizing this importance,this article analyzes and organizes the content of landscape smart lighting,delves into its system characteristics,and summarizes its principles and practices in the field of architectural engineering as practical references for application scenarios. 展开更多
关键词 Landscape smart lighting Smart city Construction engineering
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Analysis of Current Research and Future Development Trends of Applying Solar Energy in Street Lighting
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作者 Liyan Zhang Qingying Zhou +1 位作者 Yueming Zhan Hu Guo 《Journal of Electronic Research and Application》 2024年第3期191-197,共7页
In the context of promoting green energy transition and addressing climate change globally,solar energy,as a clean and renewable energy source,has gradually become a hot topic for research.Solar streetlight systems re... In the context of promoting green energy transition and addressing climate change globally,solar energy,as a clean and renewable energy source,has gradually become a hot topic for research.Solar streetlight systems realize energy self-sufficiency and environment-friendly lighting by integrating photovoltaic power generation technology and efficient LED lighting technology.By comprehensively analyzing the current status of the application of solar streetlights at home and abroad,this paper discusses its technical advantages,market penetration,and challenges in its development.In terms of technical characteristics,this paper focuses on analyzing the key technologies such as energy conversion efficiency and intelligent control systems of solar streetlights. 展开更多
关键词 Solar streetlights Green energy Photovoltaic power generation LED lighting Intelligent control system
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Application Strategies of Automatic Addressable Single-Lamp Control Technology in Tunnel Lighting
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作者 Huiyan Yang 《Journal of World Architecture》 2024年第2期90-95,共6页
The article mainly studies the application strategy of automatic addressable single-lamp control technology in tunnel lighting.It encompasses an introduction to this technology,an analysis of the tunnel lighting syste... The article mainly studies the application strategy of automatic addressable single-lamp control technology in tunnel lighting.It encompasses an introduction to this technology,an analysis of the tunnel lighting system using automatic addressable single-lamp control technology,and outlines the main development direction for this technology in modern tunnel lighting.The aim is to offer insights that can inform the rational deployment of this technology,thereby enhancing the lighting control effectiveness in modern tunnels and meeting their specific lighting requirements more effectively. 展开更多
关键词 Tunnel lighting Automatic addressable single-lamp control technology System design Cascade control
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Strategies for Applying LED Lights in Night Space Lighting for Bridges
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作者 Yingling Dai Qinghua Zhao 《Journal of World Architecture》 2024年第3期57-62,共6页
LED lights have been widely used in urban night space lighting in recent years as they are small,energy-saving,and efficient.This article explores the use of LEDs in bridge night space lighting and their application s... LED lights have been widely used in urban night space lighting in recent years as they are small,energy-saving,and efficient.This article explores the use of LEDs in bridge night space lighting and their application strategies.The aim is to offer valuable insights and references for urban planners and bridge lighting designers in China.By advancing the application of LED technology in bridge night lighting,the goal is to enhance the city’s nighttime ambiance,making the bridge an iconic landmark and a defining feature of the city. 展开更多
关键词 Bridge night space lighting LED application Color band and gradient Artistic value Online publication:July 11 2024
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负载纳米钽的液晶显示光固化聚乳酸支架制备及促成骨性能
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作者 李明哲 叶翔凌 +1 位作者 王冰 余翔 《中国组织工程研究》 CAS 北大核心 2025年第4期670-677,共8页
背景:聚乳酸因具有良好的生物相容性和可控的降解速率在生物医学工程中得到了广泛应用,然而存在机械强度低和生物活性不足等缺陷,限制了其在骨组织工程中的进一步应用。目的:构建聚乳酸/聚多巴胺/钽(PLA/PDA/Ta)骨组织工程支架,探究其... 背景:聚乳酸因具有良好的生物相容性和可控的降解速率在生物医学工程中得到了广泛应用,然而存在机械强度低和生物活性不足等缺陷,限制了其在骨组织工程中的进一步应用。目的:构建聚乳酸/聚多巴胺/钽(PLA/PDA/Ta)骨组织工程支架,探究其生物安全性和体外促成骨性能。方法:利用液晶显示光固化技术制备具有多孔结构的聚乳酸(PLA)支架,将PLA支架分别浸泡在多巴胺溶液与多巴胺-纳米钽混合溶液中分别制备聚乳酸/聚多巴胺(PLA/PDA)支架、PLA/PDA/Ta支架,表征支架的微观形貌与水接触角。将MC3T3-E1细胞分别与PLA、PLA/PDA、PLA/PDA/Ta支架共培养,进行CCK-8检测与活/死细胞染色;成骨诱导分化后,进行碱性磷酸酶、茜素红染色及成骨基因检测。结果与结论:①扫描电镜下可见3种支架均具有互连的多孔三维结构,平均孔径为200μm;PLA/PDA/Ta支架的水接触角低于PLA、PLA/PDA支架(P<0.05);②CCK-8检测显示,相较于PLA、PLA/PDA支架,PLA/PDA/Ta支架可促进细胞的增殖(P<0.05);活/死细胞染色显示3组细胞增殖良好;③碱性磷酸酶与茜素红染色显示,相较于PLA、PLA/PDA支架,PLA/PDA/Ta支架可促进细胞碱性磷酸酶的表达与矿化结节形成;RT-qPCR检测显示,相较于PLA、PLA/PDA支架,PLA/PDA/Ta支架可促进细胞骨形态发生蛋白、Runx-2及Ⅰ型胶原mRNA的表达(P<0.05,P<0.01);④结果表明,PLA/PDA/Ta支架具有优异的促细胞增殖与成骨活性。 展开更多
关键词 液晶显示光固化打印 聚乳酸 聚多巴胺 纳米钽 MC3T3-E1细胞 骨组织工程支架
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Signal and Data Processing of Television Based on Multistatic Radar Systems 被引量:1
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作者 李硕 曾涛 龙腾 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期271-275,共5页
A television based multistatic radar system is described. The commercial television transmitter is used as the illuminator in the multistatic radar system. The reflected commercial television signals are measured by ... A television based multistatic radar system is described. The commercial television transmitter is used as the illuminator in the multistatic radar system. The reflected commercial television signals are measured by an array of sensors. A data processing scheme is developed that adapts to the poor signal processing ability. The innovation is focused on the construction of the observation space, which could reduce the non linearity error. The new method leads to better system stability than the traditional one. Monte Carlo simulation is utilized and compared with the traditional method. 展开更多
关键词 multistatic radar television signal signal detection tracking and filter sequential processing
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Blood diagnostic and prognostic biomarkers in amyotrophic lateral sclerosis
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作者 Yongting Lv Hongfu Li 《Neural Regeneration Research》 SCIE CAS 2025年第9期2556-2570,共15页
Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely limited.The principal pathological alterations of the disease include the selective d... Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely limited.The principal pathological alterations of the disease include the selective degeneration of motor neurons in the brain,brainstem,and spinal cord,as well as abnormal protein deposition in the cytoplasm of neurons and glial cells.The biological markers under extensive scrutiny are predominantly located in the cerebrospinal fluid,blood,and even urine.Among these biomarke rs,neurofilament proteins and glial fibrillary acidic protein most accurately reflect the pathologic changes in the central nervous system,while creatinine and creatine kinase mainly indicate pathological alterations in the peripheral nerves and muscles.Neurofilament light chain levels serve as an indicator of neuronal axonal injury that remain stable throughout disease progression and are a promising diagnostic and prognostic biomarker with high specificity and sensitivity.However,there are challenges in using neurofilament light chain to diffe rentiate amyotrophic lateral sclerosis from other central nervous system diseases with axonal injury.Glial fibrillary acidic protein predominantly reflects the degree of neuronal demyelination and is linked to non-motor symptoms of amyotrophic lateral sclerosis such as cognitive impairment,oxygen saturation,and the glomerular filtration rate.TAR DNA-binding protein 43,a pathological protein associated with amyotrophic lateral sclerosis,is emerging as a promising biomarker,particularly with advancements in exosome-related research.Evidence is currently lacking for the value of creatinine and creatine kinase as diagnostic markers;however,they show potential in predicting disease prognosis.Despite the vigorous progress made in the identification of amyotrophic lateral sclerosis biomarkers in recent years,the quest for definitive diagnostic and prognostic biomarke rs remains a formidable challenge.This review summarizes the latest research achievements concerning blood biomarkers in amyotrophic lateral sclerosis that can provide a more direct basis for the differential diagnosis and prognostic assessment of the disease beyond a reliance on clinical manifestations and electromyography findings. 展开更多
关键词 amyotrophic lateral sclerosis BIOMARKER blood biomarkers diagnosis glial fibrillary acidic protein neurofilament light chain PROGNOSIS TAR DNA-binding protein 43
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基于锥形超晶格p-AlInGaN层的AlGaN基深紫外发光二极管性能优化
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作者 许愿 张傲翔 +3 位作者 张鹏飞 王芳 刘俊杰 刘玉怀 《原子与分子物理学报》 CAS 北大核心 2025年第1期101-107,共7页
为了解决AlGaN基深紫外(DUV)发光二极管(LED)中的严重电子溢出和低空穴注入的问题,本文提出了一种新型锥形超晶格p-AlInGaN层,它大幅改善了基于AlGaN的DUV LED的光电特性.与传统结构相比,所提出结构的输出功率提高了337.8%;同时它的内... 为了解决AlGaN基深紫外(DUV)发光二极管(LED)中的严重电子溢出和低空穴注入的问题,本文提出了一种新型锥形超晶格p-AlInGaN层,它大幅改善了基于AlGaN的DUV LED的光电特性.与传统结构相比,所提出结构的输出功率提高了337.8%;同时它的内部量子效率(IQE)也高达96%,并且没有效率下降现象.仿真计算结果表明,锥形超晶格p-AlInGaN层的引入明显增加了多量子阱(MQWs)内载流子的浓度并降低了量子阱(QWs)内的电场,导致了更高的辐射复合率,为改善DUV LED的性能提供了一个有吸引力的解决方案. 展开更多
关键词 深紫外发光二极管 ALINGAN 锥形超晶格 内部量子效率 辐射复合
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Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases
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作者 Lifang Zhao Mingkai Zhang +4 位作者 Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning Cai 《Neural Regeneration Research》 SCIE CAS 2025年第8期2373-2381,共9页
Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is k... Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results. 展开更多
关键词 Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein NEURODEGENERATION neurofilament light chain plasma biomarkers single molecule array storage time tau
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REG增强的脱细胞猪角膜/聚甲基丙烯酸羟乙酯原位一体式全层复合人工角膜
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作者 辛远 吴茜茜 +2 位作者 全亮 张亨通 敖强 《中国组织工程研究》 CAS 北大核心 2025年第16期3388-3399,共12页
背景:目前用于全层移植的人工角膜缺乏生物活性及力学适配性,组合式人工角膜存在镜柱和周围组分间的界面问题。目的:在脱细胞猪角膜原位固化制备具有多肽增强、匹配自然角膜机械强度、良好透光性的一体式全层人工角膜。方法:使用非离子... 背景:目前用于全层移植的人工角膜缺乏生物活性及力学适配性,组合式人工角膜存在镜柱和周围组分间的界面问题。目的:在脱细胞猪角膜原位固化制备具有多肽增强、匹配自然角膜机械强度、良好透光性的一体式全层人工角膜。方法:使用非离子型脱细胞试剂Triton X-100与超声冻融及超级核酸酶相结合的方法制备脱细胞猪角膜,将聚甲基丙烯酸羟乙酯单体与光引发剂同时引入脱细胞猪角膜中,通过紫外滤光片遮住除中心区域以外的部分,使用275 nm紫外光引发中央区域聚合,除去未反应的单体及引发剂后得到中央光学区,同理在后板层固化隔水区,最后引入REG活性多肽,得到原位一体式全层人工角膜,表征人工角膜的物理性能、力学性能、透光性、降解性能及体内外生物相容性。结果与结论:①实验在脱细胞猪角膜的中央区域采用聚甲基丙烯酸羟乙酯原位构建了一个具有聚合物和胶原纤维共存的光学区,扫描电镜下可见人工角膜的上表面较为粗糙且轮廓不规则,具有明显的凹陷和突起结构,下表面相对光滑;该人工角膜具有接近于天然角膜的力学性能,光学区透光率达到自然角膜的80%,浸泡于含胶原酶的PBS无菌溶液中可较好地保留固化光学区和隔水区,维持角膜的基本结构;该人工角膜具有良好的细胞相容性,能够为细胞提供适宜的黏附生长环境,有利于角膜上皮细胞的迁移和黏附,促进血管内皮细胞的生长和新生血管的形成,促进上皮化过程;人工角膜植入SD大鼠皮下12周后具有良好的生物相容性和安全性,可降低植入初期的急性炎症反应;②结果表明,实验制备的一体式全层人工角膜具有作为全层人工角膜支架材料的潜力。 展开更多
关键词 人工角膜 脱细胞猪角膜 紫外光固化 甲基丙烯酸羟乙酯 组织工程 REG多肽
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Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury
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作者 Hang Yang Yulei Xia +4 位作者 Yue Ma Mingtong Gao Shuai Hou Shanshan Xu Yanqiang Wang 《Neural Regeneration Research》 SCIE CAS 2025年第7期1900-1918,共19页
The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically revie... The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically reviewed.Here,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion injury.We further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple mechanisms.Inhibition of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury. 展开更多
关键词 calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein
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高烈度地区体育馆类公共建筑结构设计探讨
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作者 王烨妮 王固琴 《山西建筑》 2025年第1期51-54,共4页
风雨操场作为体育馆类公共建筑,通常造型独特且体型复杂;而作为乙类建筑,存在大跨度、水平和竖向刚度分布不均等结构分析中较难处理的问题,因此其计算分析较为严格,而宁夏银川作为8度区,其抗震要求则更为严格且计算分析亦更为复杂。以... 风雨操场作为体育馆类公共建筑,通常造型独特且体型复杂;而作为乙类建筑,存在大跨度、水平和竖向刚度分布不均等结构分析中较难处理的问题,因此其计算分析较为严格,而宁夏银川作为8度区,其抗震要求则更为严格且计算分析亦更为复杂。以银川一中风雨操场为例,对体育馆类结构中存在的问题及其处理方法进行了分析和探讨,为同类建筑的结构设计提供参考。 展开更多
关键词 风雨操场 体育馆 大跨度 斜柱 轻钢龙骨金属网墙体 网架屋面 钢骨架轻型板屋面
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Overhead supplemental far-red light stimulates tomato growth under intra-canopy lighting with LEDs 被引量:17
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作者 ZHANG Ya-ting ZHANG Yu-qi +1 位作者 YANG Qi-chang LI Tao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第1期62-69,共8页
Far-red(FR) light regulates phytochrome-mediated morphological and physiological plant responses.This study aims to investigate how greenhouse tomato morphology and production response to different durations of FR lig... Far-red(FR) light regulates phytochrome-mediated morphological and physiological plant responses.This study aims to investigate how greenhouse tomato morphology and production response to different durations of FR light during daytime and at the end of day(EOD).High-wire tomato plants were grown under intra-canopy lighting consisting of red(peak wavelength at 640 nm) and blue(peak wavelength at 450 nm) light-emitting diodes(LEDs) with photosynthetic photon flux density(PPFD) of 144 μmol m–2 s–1 at 10 cm away from the lamps,and combined with overhead supplemental FR light(peak wavelength at 735 nm) with PPFD of 43 μmol m–2 s–1 at 20 cm below the lamps.Plants were exposed to three durations of FR supplemental lighting including: 06:00–18:00(FR12),18:00–19:30(EOD-FR1.5),18:00–18:30(EOD-FR0.5),and control that without supplemental FR light.The results showed that supplemental FR light significantly stimulated stem elongation thereby resulting in longer plants compared with the control.Moreover,FR light altered leaf morphology toward higher leaf length/width ratio and larger leaf area.The altered plant architecture in FR supplemented plants led to a more homogeneous light distribution inside the canopy.Total plant biomass was increased by 9–16% under supplemental FR light in comparison with control,which led to 7–12% increase in ripe fruit yield.Soluble sugar content of the ripe tomato fruit was slightly decreased by longer exposure of the plants to FR light.Dry matter partitioning to different plant organs were not substantially affected by the FR light treatments.No significant differences were observed among the three FR light treatments in plant morphology as well as yield and biomass production.We conclude that under intra-canopy lighting,overhead supplemental FR light stimulates tomato growth and production.And supplementary of EOD-FR0.5 is more favorable,as it consumes less electricity but induces similar effects on plant morphology and yield. 展开更多
关键词 SOLANUM lycopersicum far-red light LEDS intro-canopy lighting morphology yield
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Effect of Television Viewing on Pediatric Obesity 被引量:5
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作者 MAGUAN-SHENG LIYAN-PING 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第4期291-297,共7页
Objective To test the effect of television viewing on pediatric obesity in urban China. Methods Stratified multistage cluster random sampling method was used for subjects selection. Nine thousand three hundred and fif... Objective To test the effect of television viewing on pediatric obesity in urban China. Methods Stratified multistage cluster random sampling method was used for subjects selection. Nine thousand three hundred and fifty-six children, as well as their parents, were investigated. Questionnaire survey was used for data collection. Children's weights and heights were measured in the clinic of the investigated kindergartens or schools by trained investigators following the standardized procedure. Results The percentages of children and adolescents who watched television less than 1 h, 1-2 h, 2-3 h and more than 3 h daily were 32.5%, 46.0%, 15.4% and 6.1%, respectively, while the prevalence of obesity was 10.9%, 11.8%, 13.2% and 15.1%, respectively. Each hourly increment of television viewing was associated with 1 %-2% increase in the prevalence of obesity. Conclusions Time spent watching television is directly related to an increase risk of obesity, television viewing time is an independent factor for pediatric obesity. 展开更多
关键词 Children and adolescent television viewing OBESITY
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