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microRNA与皮肤衰老的研究进展

中国美容医学 2024年第4期33卷 186-190页

作者：包树明(综述) 诺布央卓左蕊向小燕(审校) 川北医学院附属医院整形美容烧伤外科四川南充637000 川北医学院四川南充637000

皮肤衰老是人体衰老最直观的表现,目前已发现皮肤衰老过程中伴着microRNA(miRNA)表达的改变。这表明miRNA可能参与了皮肤衰老过程的调控,可能有用于作为皮肤衰老的标志物和抗衰老治疗策略。本文旨在探讨miRNA如何通过影响皮肤角质形成... 详细信息

皮肤衰老是人体衰老最直观的表现,目前已发现皮肤衰老过程中伴着microRNA(miRNA)表达的改变。这表明miRNA可能参与了皮肤衰老过程的调控,可能有用于作为皮肤衰老的标志物和抗衰老治疗策略。本文旨在探讨miRNA如何通过影响皮肤角质形成细胞、成纤维细胞、免疫细胞及黑素细胞的增殖、分化、细胞稳定、蛋白通路、细胞周期等方面导致皮肤的衰老。

关键词：微小RNA 衰老角质形成细胞成纤维细胞黑素细胞免疫细胞

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Bridging open source tools and Geoportals for interactive spatial data analytics

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Geo-Spatial Information Science 2019年第3期22卷 185-192页

作者： Bing She Tao Hu Xinyan Zhu shuming bao University of Michigan Ann ArborMIUSA Center for Geographical Analysis Harvard UniversityCambridgeMAUSA Geocomputation Center for Social Sciences Wuhan UniversityWuhanChina State Key Lab of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Collaborative Innovation Center of Geospatial Technology WuhanChina China Data Institute Ann ArborMIUSA

Geoportals have been the primary source of spatial information to researchers in diverse *** years have seen a growing trend to integrate spatial analysis and geovisual analytics inside *** could use the Geoportal to conduct basic analysis without offline *** practice,domain-specific analysis often requires researchers to integrate heterogeneous data sources,leverage new statistical models,or build their own customized *** tasks are increasingly being tackled with open source tools in programming languages such as Python or ***,it is unrealistic to incorporate the numerous open source tools in a Geoportal platform for data processing and *** work provides an exploratory effort to bridge Geoportals and open source tools through Python *** Geoportal demonstrated in this work is the Urban and Regional Explorer for China studies.A python package is provided to manipulate this platform in the local programming *** server side of the Geoportal implements a set of service endpoints that allows the package to upload,transform,and process user data and seamlessly integrate them into the existing datasets.A case study is provided that illustrated the use of this package to conduct integrated analyses of search engine data and baseline census *** work attempts a new direction in Geoportal development,which could further promote the transformation of Geoportals into online analytical workbenches.

关键词： Geoportal open source Python web GIS spatial analysis

Energy Dissipation and Apparent Viscosity of Semi-solid Metal during Rheological Processes PartⅠ: Energy Dissipation

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Journal of Materials Science & Technology 2007年第6期23卷 342-346页

作者： Wen LIU shuming XING Peiwei bao Milan ZHANG Liming XIAO Beijing Jiaotong University Beijing 100044 China

This study investigated the rheological properties of semi-solid metal. An analytical model of apparent viscosity was built up based on analysis of energy dissipation during rheological processes such as slurry preparing, delivering and model filling. The rheological properties of SSM (semi-solid metal) slurry was described by an analytical model in terms of microstructural parameters, which consist of effective solid fraction, particle size and shape, and flow parameters such as mean velocity, fluctuant velocity and relative velocity between liquid and solid phase. The model was verified in the experiment of A356 alloys with a coaxial double-bucket rheometer. And the maximum relative error between the theoretical value and measured one is less than 10%. The results of experiment and theoretical calculation also indicate that the microstructural parameters and flow parameters are two major factors that affect the apparent viscosity of semi-solid alloys, and fluctuant velocity and relative velocity between liquid and solid phase are the key factors to distinguish between steady and transient rheological properties.

关键词： Semi-solid metal Energy dissipation Rheology Apparent viscosity Model

A New Analytical Model for the Flow Stress of Twin-roll Casting Magnesium Sheet at Elevated Temperatures

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Journal of Materials Science & Technology 2010年第5期26卷 461-466页

作者： Zhimin Liu,shuming Xing ,Peiwei bao,Nan Li,Shuqing Yao and Milan Zhang School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing 100044,China School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing 100044 China

To evaluate the flow stress of the twin-roll casting magnesium sheet in high temperature forming processes,a new analytical model was proposed by analyzing stress-strain curves measured under various temperatures and strain *** model can be parameterized to reflect the volume fraction of semi-sold grain and sold grains undergoing *** applying the new model,the result showed that the simulated stress-strain curves fit the experiment data very *** curve fitting can be employed for any magnesium sheet when the deformation conditions are *** evolution indicated that it affected the stress-strain curves *** mechanisms of dynamic recrystallization（DRX） depended on the operating deformation mechanisms,which changed with *** the volume fraction and grain size of DRX changed with the Zener-Hollomon parameter and temperatures.

关键词： Twin-roll casting Semi-sold grains Twinning

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基于数学形态学的遥感影像人工草地提取研究

应用基础与工程科学学报 2016年第6期24卷 1075-1086页

作者：张丽华王春霞包玉海李继军高郁斌 shuming bao 内蒙古师范大学内蒙古自治区遥感与地理信息系统重点实验室内蒙古呼和浩特010022 北京师范大学水科学研究院北京100875 内蒙古工业大学理学院内蒙古呼和浩特010051 华北水利水电大学土木与交通学院河南郑州450000 China Data Center University of MichiganMIAnn Arbor 48105

以内蒙古自治区太仆寺旗为研究区,基于Landsat 8 OLI遥感影像,采用数学形态学方法构建了太仆寺旗人工草地提取模型.对内蒙古自治区太仆寺旗2013年8月23日的遥感影像进行了几何精校正、辐射定标、大气校正等预处理,并进行了归一化植被指... 详细信息

以内蒙古自治区太仆寺旗为研究区,基于Landsat 8 OLI遥感影像,采用数学形态学方法构建了太仆寺旗人工草地提取模型.对内蒙古自治区太仆寺旗2013年8月23日的遥感影像进行了几何精校正、辐射定标、大气校正等预处理,并进行了归一化植被指数NDVI计算.在分析太仆寺旗人工草地几何特征的基础上,采用数学形态学方法对NDVI梯度图像进行了边缘检测,得到了边缘NDVI梯度图,并对其进行了二值化处理.基于圆环形结构元素构建了太仆寺旗人工草地提取模型,从NDVI梯度图的二值图像中提取了形状规则的圆形人工草地,并与太仆寺旗人工草地实际数目与面积进行了比较.结果表明,提取数目精度达到93.73%,提取面积精度达到92.16%,说明本文提出的基于遥感影像与数学形态学的人工草地提取模型,可有效地提取太仆寺旗的人工草地.

关键词：遥感影像人工草地数学形态学几何特征提取太仆寺旗

Detection on Resources Consumption Drag of Urbanization in China

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Natural Resources 2010年第2期1卷 80-87页

作者： Yaobin Liu Guixin Wang shuming bao 不详

A unique model of resources consumption drag of urbanization is developed by employing the neo-classical production model and the urbanization relation model. By using this model, it is viable to estimate the resources consumption drag, measured as the reduced speed of urbanization from resources consumption and environmental services. In terms of reduced urbanization process, the aggregated and disaggregated effects from some crucial resources, such as energy, land and water, are calculated and presented. The results show that the drags from energy consumption, land and water in process of China’s urbanization are 0.1061, 0.0036 and 0.1914 percent point respectively and the aggregate drag arrives 0.3010 percent point. With the increasing population and the developing urbanization process in China, the constraints of resources, water and energy in particular cannot be eliminated and the drags will be enhanced and hence the pressure of further urbanization process is still a relatively serious problem.

关键词： Urbanization Rresources Consumption Drag Economic Growth Model Urbanization Relation Model

制造业转型升级视角下数字经济对绿色技术创新的影响

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科技管理研究 2023年第16期43卷 215-222页

作者：束云霞吴玉鸣鲍曙明华东理工大学商学院上海200237

为向进一步落实兼顾创新与绿色双重发展理念提供理论和现实依据,利用2011—2020年中国280个地级市的面板数据,从禀赋效应、赋能效应、治理效应和社会效应4个方面,通过固定效应模型和中介效应模型探讨数字经济对绿色技术创新的影响效果... 详细信息

为向进一步落实兼顾创新与绿色双重发展理念提供理论和现实依据,利用2011—2020年中国280个地级市的面板数据,从禀赋效应、赋能效应、治理效应和社会效应4个方面,通过固定效应模型和中介效应模型探讨数字经济对绿色技术创新的影响效果和传导机制,同时从城市区域、经济规模和绿色技术创新水平角度分析其异质性影响。结果发现:280个城市的数字经济显著促进绿色技术创新发展,其主要通过制造业要素密集转型升级和制造业污染密集转型升级间接促进绿色技术创新的发展;数字经济对绿色技术创新的影响存在异质性,相比东部地区、经济规模和绿色技术创新水平较低的城市,数字经济对中西部地区、经济规模和绿色技术创新水平较高城市的绿色技术创新促进作用更为显著。由此建议政府加大数字经济发展所需的财税、金融、保险、法律等配套制度保障力度,同时进一步优化数字经济应用场景,并且“因城施策”,推动区域制造业产业实现绿色转型。

关键词：数字经济绿色技术创新制造业转型升级

Human mobility data in the COVID-19 pandemic:characteristics,applications,and challenges

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International Journal of Digital Earth 2021年第9期14卷 1126-1147页

作者： Tao Hu Siqin Wang Bing She Mengxi Zhang Xiao Huang Yunhe Cui Jacob Khuri Yaxin Hu Xiaokang Fu Xiaoyue Wang Peixiao Wang Xinyan Zhu shuming bao Wendy Guan Zhenlong Li Department of Geography Oklahoma State UniversityStillwaterOKUSA Center for Geographic Analysis Harvard UniversityCambridgeMAUSA School of Earth and Environmental Sciences The University of QueenslandSt LuciaAustralia Institute for Social Research University of MichiganAnn ArborMIUSA School of Health Ball State UniversityMuncieINUSA Department of Geosciences University of ArkansasFayettevilleARUSA Department of Geography University of ConnecticutStorrsCTUSA Lake Erie College of Osteopathic Medicine Seton Hill UniversityGreensburgPAUSA School of Resource and Environmental Sciences Wuhan UniversityWuhanPeople’s Republic of China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanPeople’s Republic of China China Data Institute Ann ArborMIUSA Geoinformation and Big Data Research Laboratory Department of GeographyUniversity of South CarolinaColumbiaSCUSA

The COVID-19 pandemic poses unprecedented challenges around the *** studies have applied mobility data to explore spatiotemporal trends over time,investigate associations with other variables,and predict or simulate the spread of *** objective was to provide a comprehensive overview of human mobility open data to guide researchers and policymakers in conducting data-driven evaluations and decision-making for the COVID-19 pandemic and other infectious disease *** summarized the mobility data usage in COVID-19 studies by reviewing recent publications on COVID-19 and human mobility from a data-oriented *** identified three major sources of mobility data:public transit systems,mobile operators,and mobile phone *** approaches have been commonly used to estimate human mobility:public transit-based flow,social activity patterns,index-based mobility data,and social media-derived mobility *** compared mobility datasets’characteristics by assessing data privacy,quality,space–time coverage,high-performance data storage and processing,and *** also present challenges and future directions of using mobility *** review makes a pivotal contribution to understanding the use of and access to human mobility data in the COVID-19 pandemic and future disease outbreaks.

关键词： COVID-19 public health human mobility open data mobile phone mobility index

运用证据权重法进行阳性钉螺-地理因子的空间关系研究(英文)

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Geo-Spatial Information Science 2009年第3期12卷 217-224页

作者：赵安鲍曙明宫鹏 School of Geography and Environmental Science Jiangxi Normal University Key Lab of Poyang Lake Wetland and Watershed Research Jiangxi Normal University and Ministry of Education

Schistosomiasis is a serious public health problem in the middle-lower Yangtze River Basin in China. Study of spatial variation of snail distribution that is related to microgeographic factors can help to choose pertinent measures for snail extinguishment and environment rebuilding. This paper studied the theoretical architecture of weights-of-evidence approach. The case study was made for spatial relation between the occurrence of infected snails and geographic factor combinations in Waijiazhou marshland of Poyang Lake region in China. The multievidence data came from the geographical factor combinations by crossing operation of vegetation coverage grade layer, cattle route distance grade layer, and special environment layer (181 combinations in total) in GIS. The calculation of weight contrast index shows that high vegetation coverage, cattle route distance of <45 meters, and special geographic factor "ground depression" had direct spatial relation with the occurrence of infected snails. The verification by crossing operation in GIS indicated 72.45% of the infected snails concentrated on the areas of positive weight contrast index (sequenced in an order of weight contrast index from high to low), demonstrating the high efficiency of the model established in finding infected snails according to the geographic factor combinations that can be explicitly discerned in the study area.

关键词：地理因素钉螺分布空间关系感染性权重证据地理信息系统植被覆盖度