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Local field potentials,spiking activity,and receptive fields in human visual cortex

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Science china(Life sciences) 2024年第3期67卷 543-554页

作者： Lu Luo Xiongfei Wang Junshi Lu Guanpeng Chen Guoming luan Wu Li Qian Wang Fang Fang school of Psychological and Cognitive sciences and beijing Key Laboratory of Behavior and Mental Health Peking UniversityBeijing 100871China school of Psychology Beijing Sport UniversityBeijing 100084China Department of Neurosurgery Sanbo Brain HospitalCapital Medical UniversityBeijing 100093China beijing Key Laboratory of Epilepsy Epilepsy CenterSanbo Brain HospitalCapital Medical UniversityBeijing 100093China IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China Peking-Tsinghua Center for Life sciences Peking UniversityBeijing 100871China beijing Institute for Brain Disorders Beijing 100069China State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China

The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs with intracranial local field potentials(LFPs) and spiking activity in human visual cortex(V1/V2/V3). We recorded LFPs via macro-contacts and discovered that RF sizes estimated from lowfrequency activity(LFA, 0.5–30 Hz) were larger than those estimated from low-gamma activity(LGA, 30–60 Hz) and high-gamma activity(HGA, 60–150 Hz). We then took a rare opportunity to record LFPs and spiking activity via microwires in V1 simultaneously. We found that RF sizes and temporal profiles measured from LGA and HGA closely matched those from spiking activity. In sum, this study reveals that spiking activity of neurons in human visual cortex could be well approximated by LGA and HGA in RF estimation and temporal profile measurement, implying the pivotal functions of LGA and HGA in early visual information processing.

关键词： human visual cortex receptive field intracranial EEG local field potential spiking activity

我国教育博士培养制度的建立动因、发展阶段与价值取向

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湖州师范学院学报 2024年第6期46卷 1-8页

作者：高鸾朱旭东湖州师范学院教师教育学院浙江湖州313000 北京师范大学教师教育研究中心北京100875

教育博士培养制度作为我国教师教育体系的重要组成部分,自2009年建立以来不仅满足了教育事业发展对不同类型教育高端人才的需求,而且促进了学位与研究生教育结构的优化。为深化对我国教育博士培养制度的认识与理解,本文选取我国部分教... 详细信息

教育博士培养制度作为我国教师教育体系的重要组成部分,自2009年建立以来不仅满足了教育事业发展对不同类型教育高端人才的需求,而且促进了学位与研究生教育结构的优化。为深化对我国教育博士培养制度的认识与理解,本文选取我国部分教育博士培养院校进行深入调研,揭示了该制度建立的内外动因及其发展阶段。我国教育博士培养制度建立的外部动因是为了适应时代发展对优秀教师的需求,并受到西方主要国家教育博士培养经验的启发;内部动因则与国内经济社会发展、劳动力市场需求变化及民众对优质教育的增长需求紧密相关。该制度的发展分三个阶段:以学习和借鉴美国模式为主的孕育探索期(1999-2008年);国家统筹与院校探索相结合的试点培养期(2009-2015年);以适应需求和质量提升为重点的持续发展期(2016年至今)。在我国教育博士培养制度建立与发展过程中,政治与学术精英组成的政策支持联盟对制度的建立和发展起到了关键作用。教育博士培养制度的建立与发展体现出对教师实践性知识的重视和对知识实践性的强调,是一种对社会发展需求的回应。

关键词：教育博士培养制度建立动因发展阶段价值取向

Spatiotemporal evolution and prediction of habitat quality in Hohhot City of china based on the InVEST and CA-Markov models

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Journal of Arid Land 2023年第1期15卷 20-33页

作者： luan Yongfei HUANG Guohe ZHENG Guanghui College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China school of Environment Beijing Normal UniversityBeijing 100875China school of Architecture and Art Central South UniversityChangsha 410083China

With the acceleration of urbanization,changes in the urban ecological environment and landscape pattern have led to a series of prominent ecological environmental *** order to better coordinate the balanced relationship between city and ecological environment,we selected land use change data to evaluate the habitat quality in Hohhot City of china,which is of great practical significance for regional urban and economic ***,the integrated valuation of ecosystem services and tradeoffs(InVEST)and Cellular Automata-Markov(CA-Markov)models were used to analyze,predict,and explore the Spatiotemporal evolution path and characteristics of urban land use,and forecast the typical evolution pattern of land use in *** results showed that the land use types in Hohhot City changed significantly from 2000 to 2020,and the biggest change took place in cultivated land,grassland,shrub,and artificial *** decrease of cultivated land area and the increase of artificial surface area were the main impact trend of land use *** average value of habitat quality had been decreasing continuously from 2000 to 2020,and the values of habitat degradation were 0.2605,0.2494,and 0.2934 in 2000,2010,and 2020,respectively,showing a decreasing *** decrease of habitat quality was caused by the needs of economic development and urban construction,as well as the impact of land *** this evolution,many cultivated land and urban grassland had been converted into construction *** simulated land use changes in 2030 are basically the same as those during 2000-2020,and the habitat quality will still be *** regional changes are influenced by the urban rapid development and industrial *** results can provide decision-making reference for regional urban planning and management as well as habitat quality evaluation.

关键词： land use urbanization InVEST CA-Markov habitat quality Hohhot City

Spatial impacts of climate factors on regional agricultural and forestry biomass resources in north-eastern province of china

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Frontiers of Environmental Science & Engineering 2016年第4期10卷 91-104页

作者： Wenyan Wang Wei Ouyang Fanghua Hao Yun luan Bo Hu school of Environment State Key Laboratory of Water Environment Simulation Beijing Normal University Beijing 100875 China beijing Zhongchi Green Energy and Environmental Technology Co. Ltd. Golden Resources Office Building Beijing 100097 China The Administrative Center for china's Agenda 21 Ministry of Science and Technology of the People's Republic of China Beijing 100038 China Department of Soil and Water Conservation Changjiang River Scientific Research Institute Wuhan 430019 China

The dynamics of agricultural and forestry biomass are highly sensitive to climate change, particularly in high latitude regions. Heilongjiang Province was selected as research area in North-east china. We explored the trend of regional climate warming and distribution feature of biomass resources, and then analyzed on the spatial relationship between climate factors and biomass resources. Net primary productivity （NPP） is one of the key indicators of vegetation productivity, and was simulated as base data to calculate the distribution of agricultural and forestry biomass. The results show that temperatures rose by up to 0.37℃/10a from 1961 to 2013. Spatially, the variation of agricultural biomass per unit area changed from -1.93 to 5.85 ***^-2.a^-1 during 2000,2013. More than 85% of farmland areas showed a positive relationship *** agricultural biomass and precipitation. The results suggest that precipitation exerts an overwhelming climate influence on agricultural biomass. The mean density of forestry biomass varied from 10 to 30 t·km^-2. Temperature had a significant negative effect on forestry biomass in Lesser Khingan and northern Changbai Mountain, because increased temperature leads to decreased Rubisco activity and increased respiration in these areas. Precipitation had a significant positive relationship with forestry biomass in south-western Changbai Mountain, because this area had a wanner climate and stress from insufficient precipitation may induce xylem cavitation. Understanding the effects of climate factors on regional biomass resources is of great significance in improving environmental management and promoting sustainable development of further biomass resource use.

关键词： Biomass resourcesNet primary productivity (NPP)Climate change Heilongjiang Province china

天文旋回约束下东营凹陷中始新统含碳酸盐细粒沉积岩成因分析

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沉积学报 2024年第2期42卷 688-700页

作者：栾旭伟孔祥鑫张金亮蒋龙彭艳霞蔡媛中国地质大学(北京)能源学院北京100083 北京师范大学地理科学学部自然资源学院北京100875 中石化胜利油田山东东营257000 南京大学地球科学与工程学院南京210023

【目的】通过对中国东部渤海湾盆地东营凹陷发育的大套具有韵律特征的富含碳酸盐物质和有机质的湖相细粒沉积岩进行深入研究,以期探究其成因机制以及古气候、古环境的变化特征。【方法】基于岩心和薄片观察,依据沉积构造特征和矿物组分... 详细信息

【目的】通过对中国东部渤海湾盆地东营凹陷发育的大套具有韵律特征的富含碳酸盐物质和有机质的湖相细粒沉积岩进行深入研究,以期探究其成因机制以及古气候、古环境的变化特征。【方法】基于岩心和薄片观察,依据沉积构造特征和矿物组分含量进行岩相划分。结合沉积环境和沉积速率的差异,将目标层段划分为四个单元,采取Multi-Taper Method(MTM)方法对樊页1井(FY1)沙四上(Esu4)到沙三下(Esl3)亚段的自然伽马(GR)测井曲线进行分段频谱分析。【结果】通过宏观和微观沉积观察,将东营凹陷地区发育的细粒岩划分为纹层状泥质灰岩、纹层状灰质泥岩、弱纹层状灰质泥岩、透镜状泥质灰岩和块状泥岩五种岩相。频谱分析结果显示,四个单元均记录了米兰科维奇旋回信号,包括125 kyr、38.7 kyr和18.7 kyr的周期。基于火山灰测年数据,我们建立了精度为38.7 kyr的“浮动”天文年代标尺,并确定东营凹陷沙四上到沙三下细粒岩沉积的总持续时间为5.3 Myr。进一步分析发现,18.7 kyr岁差旋回与碳酸盐岩含量变化之间存在良好的对应关系,表明地球轨道参数对含碳酸盐细粒沉积岩的沉积作用具有显著影响。【结论】本研究利用旋回地层学理论,从天文周期控制沉积作用的角度,揭示了湖泊沉积的古气候、古环境变化特征。通过分析,我们发现地球轨道参数(特别是18.7 kyr岁差旋回和125 kyr偏心率旋回)共同驱动了气候的变化,进而控制了含碳酸盐细粒沉积岩的沉积作用。具体表现为,在岁差极大值点或偏心率极小值处,日照量增多,湖盆水体温度升高,有利于方解石结晶和灰岩沉积;而在岁差极小值或偏心率极大值处,日照量减少,湖盆水体温度降低,细粒物质主要来自陆源输入,以泥岩沉积为主。这一研究成果对于非常规油气勘探开发具有重要的科学和指导意义。

关键词：旋回地层学东营凹陷 “浮动”天文年代标尺含碳酸盐细粒沉积岩

Factors and mechanism driving the land-use conversion in Jiangxi Province

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Journal of Geographical sciences 2010年第4期20卷 525-539页

作者： ZHAN Jinyan SHI nana HE Shujin LIN Yingzhi State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China Institute of Geographic sciences and Natural Resources Research CAS Beijing 100101 China

This article explores the factors and mechanism driving the land-use conversion at regional level by developing and using an econometric approach which is called the simultaneous equations model （SEM）. A case study in Jiangxi Province of china is conducted by establishing the SEM, which consists of three equations including agricultural production, land conversion of cultivated land to built-up area and land conversion of cultivated land to forest cover/grassland from 1988 to 2005. And then this paper employs the method of piecewise estimation to represent the influences of the factors such as population, society, economy, location and geophysical conditions on the process of land-use conversion in Jiangxi Province. Estimation results show that population is a predominant factor driving the land-use conversion at counties, while social and economic factors are determinant factors in the short term for the entire Jiangxi Province. Specifically, the size of agricultural population and the magnitude of agricultural input determine the agricultural production to a large extent; population size, plain area proportion at counties and land management policies together affect the direction and magnitude of conversion between cultivated land and built-up area; agricultural population proportion, terrain slope, grain production and non-agricultural industry promote the conversion of cultivated land to forest cover/grassland. Furthermore, the explored mechanism also reveals the underlying causes of the land use changes driven by a series of factors in Jiangxi Province. Finally, this paper concludes that factors proven to play an important role in driving the land-use conversion need to be considered when the land management agencies make out the land use planning to optimize the land use, expand the agricultural production, and conserve the cultivated land.

关键词： land use land-use conversion mechanism econometric model simultaneous equations model Jiangxi Province

环境约束下京津冀区域经济发展质量测度与动力解构——基于绿色全要素生产率视角

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经济地理 2020年第9期40卷 36-45页

作者：蔺鹏孟娜娜北京师范大学经济与工商管理学院中国北京100875 中国邮政集团公司培训中心中国河北石家庄050021

以绿色全要素生产率为研究基点,利用京津冀城市群2001—2015年面板数据,构建超越对数生产函数SFA模型对京津冀区域经济发展质量与增长动力进行实证评估与分析解构。研究发现:京津冀绿色全要素生产率的增长率区域差异显著,且考虑环境因... 详细信息

以绿色全要素生产率为研究基点,利用京津冀城市群2001—2015年面板数据,构建超越对数生产函数SFA模型对京津冀区域经济发展质量与增长动力进行实证评估与分析解构。研究发现:京津冀绿色全要素生产率的增长率区域差异显著,且考虑环境因素的绿色全要素生产率增速明显低于传统全要素生产率。技术进步并未成为驱动京津冀区域经济增长的核心动能,技术效率与配置效率对该区域经济发展的贡献较为微弱,要素规模报酬成为主导京津冀区域经济发展质量的关键因素。因此,为实现京津冀区域经济可持续增长和高质量发展,需要注重以绿色全要素生产率提升为核心,在强化技术创新能力同时兼顾技术效率改进,在优化要素禀赋结构同时兼顾要素配置效率改善,在有效实施环境规制政策同时注重环境治理效果提升,以此引导区域产业结构转型升级与经济结构优化调整,进而驱动京津冀协同发展和一体化建设有序推进。

关键词：环境约束绿色全要素生产率经济增长动力经济高质量发展京津冀区域一体化产业转型升级

技术创新与制度创新的耦合:英国智慧医疗发展模式探析

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河北学刊 2019年第6期39卷 149-154页

作者：尹栾玉王依娜北京师范大学中国社会管理研究院/社会学院

智慧医疗是综合运用物联网、互联网、云计算、大数据等技术,实现医疗信息互联、共享协作、临床创新、诊断科学以及公共卫生预防等目标的系统工程。英国在全民免费医疗的体系基础上,抓住现代技术革命的契机,不断创新制度模式,形成了引领... 详细信息

智慧医疗是综合运用物联网、互联网、云计算、大数据等技术,实现医疗信息互联、共享协作、临床创新、诊断科学以及公共卫生预防等目标的系统工程。英国在全民免费医疗的体系基础上,抓住现代技术革命的契机,不断创新制度模式,形成了引领未来的智慧医疗新范式。科技发展为英国医疗制度转型提供技术支撑,制度转型又为智慧医疗技术创新降低交易费用和摩擦成本,提供更为优化的社会环境。制度创新和技术创新互相促进、深度耦合的医疗服务模式,成为英国智慧医疗迅速高效发展的双重引擎。其成功经验和模式值得思考及借鉴。

关键词：智慧医疗技术创新制度创新

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我国教育博士培养制度实施中的问题与对策

教育发展研究 2019年第3期39卷 62-70页

作者：高鸾朱旭东湖州师范学院教师教育学院湖州313000 北京师范大学教师教育研究中心北京100875

2015年底,我国教育博士第一轮试点培养期结束,国家对15家试点培养单位进行了审核评估并启动了新一轮培养工作。作为新生事物,我国教育博士培养制度在实施过程中遇到了各种各样的问题,不仅有与美国经验类似的"培养目标争议"、"学习进度滞... 详细信息

2015年底,我国教育博士第一轮试点培养期结束,国家对15家试点培养单位进行了审核评估并启动了新一轮培养工作。作为新生事物,我国教育博士培养制度在实施过程中遇到了各种各样的问题,不仅有与美国经验类似的"培养目标争议"、"学习进度滞后"问题,也有在中国独特社会文化背景下的"大学办学自主权与制度建设问题"等。研究发现,产生问题的主要原因是学习者目标和培养机构定位的差异、学习者的有效时间投入不足和复杂的学习环境、政府政策部门的"怕乱"心理以及制度初创期的局限性等。研究基于大量文献与实证调研数据,讨论了教育博士"双重属性"作为一种解决培养目标争议的思路的可能性,提出了构建学习网络促进教育博士生的学习与研究、尝试进行制度规约之下的特色化培养实践等对策建议。

关键词：教育博士培养目标学习进度办学自主制度建设