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丹参素对UVB诱导的皮肤光老化小鼠的保护作用和抗氧化机制研究

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日用化学工业（中英文） 2024年第1期54卷 65-72页

作者：王安娜方梦婕唐超岳天翔江西省医药学校江西南昌330020 江西中医药大学江西南昌330004

研究丹参素(DSS)对紫外线B(UVB)诱导的皮肤光老化(SP)小鼠的保护作用和抗氧化机制。建立了UVB诱导的SP小鼠模型,使用3个剂量的DSS(20,40和80 mg/(kg·d))治疗小鼠8周,结束后分别测定了各组小鼠的表皮含水量。通过HE染色评价皮肤组织形态... 详细信息

研究丹参素(DSS)对紫外线B(UVB)诱导的皮肤光老化(SP)小鼠的保护作用和抗氧化机制。建立了UVB诱导的SP小鼠模型,使用3个剂量的DSS(20,40和80 mg/(kg·d))治疗小鼠8周,结束后分别测定了各组小鼠的表皮含水量。通过HE染色评价皮肤组织形态,Masson三色染色评价胶原蛋白沉积。按照试剂盒说明测定皮肤组织中氧化应激指标(SOD、CAT、GSH-Px和MDA)和炎症指标(TNF-α和IL-6)水平。通过RT-qPCT和Western blotting检测了皮肤组织中MMP-1、Collagen I、Nrf2、Keap1、HO-1、NF-κB p65和p-NF-κB p65的mRNA或蛋白水平。结果显示,DSS剂量依赖性地提高了UVB诱导的SP小鼠表皮含水量,减轻皮肤损伤,促进胶原形成(P<0.05)。DSS抑制了UVB诱导的SP小鼠皮肤组织中MMP-1的转录和表达,促进了Collagen的转录和表达(P<0.05)。DSS升高了UVB诱导的SP小鼠皮肤组织中SOD、CAT和GSH-Px的水平,降低了MDA的水平(P<0.05)。DSS降低了UVB诱导的SP小鼠皮肤组织中TNF-α和IL-6的水平(P<0.05)。DSS促进了UVB诱导的SP小鼠皮肤组织中Nrf2和HO-1的转录和表达,抑制了Keap1的转录和表达(P<0.05)。DSS抑制了UVB诱导的SP小鼠皮肤组织中p-NF-κB p65的表达(P<0.05)。本研究表明DSS可有效改善UVB诱导的小鼠SP,其机制与Nrf2和NF-κB信号通路有关。

关键词：丹参素紫外线B 皮肤光老化小鼠抗氧化

HASM-AD Algorithm Based on the Sequential Least Squares

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Geo-Spatial Information Science 2010年第4期13卷 285-293页

作者： WANG Shihai yue tianxiang Institute of Geographic Science and Natural Resource Research Chinese Academy of Science Beijing 100101 China

The HASM(high accuracy surface modeling) technique is based on the fundamental theory of surfaces,which has been proved to improve the interpolation accuracy in surface ***,the integral iterative solution in previous studies resulted in high temporal complexity in computation and huge memory usage so that it became difficult to put the technique into application,especially for large-scale *** the study,an innovative model(HASM-AD) is developed according to the sequential least squares on the basis of data adjustment *** division is adopted in the technique,so that linear equations can be divided into groups to be processed in sequence with the temporal complexity reduced greatly in *** experiment indicates that the HASM-AD technique surpasses the traditional spatial interpolation methods in ***,the cross-validation result proves the same conclusion for the spatial interpolation of soil PH property with the data sampled in Jiangxi ***,it is demonstrated in the study that the HASM-AD technique significantly reduces the computational complexity and lessens memory usage in computation.

关键词： surface modeling HASM spatial interpolation sequential least squares

Space- and ground-based CO_2 measurements： A review

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Science China Earth Sciences 2016年第11期59卷 2089-2097页

作者： yue tianxiang ZHANG LiLi ZHAO MingWei WANG YiFu John WILSON State Key Laboratory of Resources and Environment Information System Institute of Geographical Science and Natural Resources Research Beijing 100101 China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210046 China Anhui Center for Collaborative Innovation in Geographical Information Integration and Application Chuzhou University Chuzhou 239012 China Spatial Sciences Institute University of Southern California Los Angles CA90089-0374 USA

The climate warming is mainly due to the increase in concentrations of anthropogenic greenhouse gases, of which CO_2 is the most important one responsible for radiative forcing of the climate. In order to reduce the great estimation uncertainty of atmospheric CO_2 concentrations, several CO_2-related satellites have been successfully launched and many future greenhouse gas monitoring missions are planned. In this paper, we review the development of CO_2 retrieval algorithms, spatial interpolation methods and ground observations. The main findings include: 1) current CO_2 retrieval algorithms only partially account for atmospheric scattering effects; 2) the accurate estimation of the vertical profile of greenhouse gas concentrations is a long-term challenge for remote sensing techniques; 3) ground-based observations are too sparse to accurately infer CO_2 concentrations on regional scales; and 4) accuracy is the primary challenge of satellite estimation of CO_2 concentrations. These findings, taken as a whole, point to the need to develop a high accuracy method for simulation of carbon sources and sinks on the basis of the fundamental theorem of Earth's surface modelling, which is able to efficiently fuse space- and ground-based measurements on the one hand and work with atmospheric transport models on the other hand.

关键词： Accuracy Carbon satellites Retrieval algorithms Space-and ground-based measurements HASM

An improved HASM method for dealing with large spatial data sets

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Science China Earth Sciences 2018年第8期61卷 1078-1087页

作者： Na ZHAO tianxiang yue Chuanfa CHEN Miaomiao ZHAO Zhengping DU State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application Nanjing 210023 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100101 China Geomatics College Shandong University of Science and Technology Qingdao 266510 China

Surface modeling with very large data sets is challenging. An efficient method for modeling massive data sets using the high accuracy surface modeling method(HASM) is proposed, and HASM_Big is developed to handle very large data sets. A large data set is defined here as a large spatial domain with high resolution leading to a linear equation with matrix dimensions of hundreds of thousands. An augmented system approach is employed to solve the equality-constrained least squares problem(LSE) produced in HASM_Big, and a block row action method is applied to solve the corresponding very large matrix equations.A matrix partitioning method is used to avoid information redundancy among each block and thereby accelerate the *** including numerical tests and real-world applications are used to compare the performances of HASM_Big with its previous version, HASM. Results show that the memory storage and computing speed of HASM_Big are better than those of HASM. It is found that the computational cost of HASM_Big is linearly scalable, even with massive data sets. In conclusion,HASM_Big provides a powerful tool for surface modeling, especially when there are millions or more computing grid cells.

关键词： Surface modeling HASM Large spatial data

森林资源优势地区的生态系统生产总值变化及其对土地利用变化的响应:以江西省资溪县为例

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应用生态学报 2024年第8期35卷 2197-2205页

作者：朱美青岳天祥黄宏胜李鸣张瑛史文娇张永寿江西农业大学国土资源与环境学院南昌330045 中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101 江西省农业气象中心南昌330096 江西省国土资源测绘工程总院有限公司南昌330299

森林是最重要的陆地生态系统类型之一,在生态文明建设中具有举足轻重的地位,研究独具森林资源优势地区的生态系统生产总值(GEP)变化及其对土地利用变化的响应对促进该类区域可持续发展具有重要意义。本研究以江西省资溪县为研究区,基于... 详细信息

森林是最重要的陆地生态系统类型之一,在生态文明建设中具有举足轻重的地位,研究独具森林资源优势地区的生态系统生产总值(GEP)变化及其对土地利用变化的响应对促进该类区域可持续发展具有重要意义。本研究以江西省资溪县为研究区,基于生态系统价值核算理论和方法,在调节服务通用指标体系(水源涵养、土壤保持、氧气提供、碳固定、气候调节、洪水调蓄、水质净化、空气净化、物种保育)及文化服务通用指标体系(景观游憩、教育)基础上,增加负氧离子、康养等指标,并引入森林生态系统服务修正系数,构建独具森林资源优势的GEP指标体系和方法,评估了研究区2010、2017和2020年GEP的时空变化特征,采用弹性指数及价值损益分析方法量化了土地利用/土地覆盖变化对GEP的影响。结果表明:2010、2017和2020年资溪县GEP分别为167.88、268.17和384.07亿元。各生态系统GEP占总GEP比例依次为森林>湿地>农田>草地>城镇。研究期间,GEP增加值主要来源于森林生态系统。土地利用变化对GEP产生了重要影响。2010-2020年,研究区土地利用变化总面积为8501.88hm^(2)。各土地利用变化幅度依次为草地(-2811.17hm^(2))>城镇(1428.06hm^(2))>森林(1357.67hm^(2))>湿地(1031.05hm^(2))>农田(-1005.01hm^(2))。各类用地的绝对变化主要发生在2017-2020年。各测算指标对森林生态系统的弹性指数明显高于其他生态系统,说明GEP对林地面积变化的敏感性最高。价值损益分析表明,城市开发在一定程度上降低了GEP,林地、湿地的保护促进了GEP增加。2010-2020年,资溪县土地利用类型之间的转化导致GEP增加18.65亿元,说明资溪县土地利用变化整体上对生态的影响是正向的。研究结果一定程度上体现了资溪县成为国家生态文明建设示范县之后的绿色发展成效,也为研究区今后高质量发展、高水平保护和土地资源可持续开发利用提供了决策支持,并可为其他类似地区的GEP核算提供借鉴。

关键词：森林资源生态系统生产总值土地利用

A high-accuracy method for simulating the XCO_2 global distribution using GOSAT retrieval data

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Science China Earth Sciences 2017年第1期60卷 143-155页

作者： ZHAO MingWei ZHANG XingYing yue tianxiang WANG Chun JIANG Ling SUN JingLu Anhui Center for Collaborative Innovation in Geographical Information Integration and Application Chuzhou University National Satellite Meteorology Center China Meteorological Administration State Key Laboratory of Resources and Environment Information System Institute of Geographical Science and Natural Resources ResearchChinese Academy of Sciences Anhui Institute of Economics

A high-accuracy surface modeling （HASM） method based on the fimdamental theorem of surfaces, is developed to simulate XCO2 surfaces using the GOSAT retrieval XCO2 data. Two tests are designed to investigate the simulation accuracy. The first test divides the existing satellite retrieval XCO2 data into training points and testing points, and simulates the XCO2 surface using the training points while computing the simulation error using the testing points. The absolute mean error （MAE） of the testing points is 1.189 ppmv, and the corresponding values of the comparison methods, Ordinary Kriging, IDW, and Spline are 1.203, 1.301, and 1.355 ppmv, respectively. The second test simulates the XCO2 surface using all the satellite retrieval points and uses the TCCON （Total Carbon Column Observing Network） site observation values as the ture values. For the six typical TCCON sites, the HASM simulation MAE is 1.688 ppmv, and the satellite retrieval MAE at the same sites is 2.147 ppmv. These results indicate that HASM can successfully simulate XCO2 surfaces based on satellite retrieval data.

关键词： HASM GOSAT TCCON XCO2 surface

Scenarios of land cover in Eurasia under climate change

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Journal of Geographical Sciences 2020年第1期30卷 3-17页

作者： FAN Zemeng BAI Ruyu yue tianxiang State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

The method for surface modelling of land cover scenarios(SMLCS)has been improved to simulate the scenarios of land cover in *** the basis of the observation monthly climatic data observed from 2127 weather stations in Eurasia during 1981-2010,the climatic scenarios data of RCP26,RCP45 and RCP85 scenarios released by CMIP5,and the land cover current data of Eurasia in 2010,the land cover scenarios of Eurasia were respectively *** results show that most land cover types would generally have similar changing trends in the future,but with some difference in different periods under the three scenarios of RCP26,RCP45 and *** needleleaf forest,mixed forest,shrub land,wetlands and snow and ice would generally decrease in Eurasia during *** and ice would have the fastest decreasing rate that would decrease by 37.42%on *** land would have the slowest decreasing rate that would decrease by 5.65%on *** bodies would have the fastest increasing rate that would increase by 28.78%on *** or sparsely vegetated land would have the slowest increasing rate that would increase by 0.76%.Moreover,the simulated results show that climate change would directly impact on land cover change in Eurasia.

关键词： SMLCS climate change land cover scenarios Eurasia

Sensitivity studies of a high accuracy surface modeling method

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Science China Earth Sciences 2014年第10期57卷 2386-2396页

作者： ZHAO Na yue tianxiang ZHAO MingWei DU ZhengPing FAN ZeMeng CHEN ChuanFa State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Geomatics College Shandong University of Science and Technology

The sensitivities of the initial value and the sampling information to the accuracy of a high accuracy surface modeling(HASM) are investigated and the implementations of this new modeling method are modified and enhanced. Based on the fundamental theorem of surface theory, HASM is developed to correct the error produced in geographical information system and ecological modeling process. However, the earlier version of HASM is theoretically incomplete and its initial value must be produced by other surface modeling methods, such as spline, which limit its promotion. In other words, we must use other interpolators to drive HASM. According to the fundamental theorem of surface theory, we modify HASM, namely ***, by adding another important nonlinear equation to make it independent of other methods and, at the same time, have a complete and solid theory foundation. Two mathematic surfaces and monthly mean temperature of 1951–2010 are used to validate the effectiveness of the new method. Experiments show that the modified version of HASM is insensitive to the selection of initial value which is particular important for HASM. We analyze the sensitivities of sampling error and sampling ratio to the simulation accuracy of ***. It is found that sampling information plays an important role in the simulation accuracy of ***. Another feature of the modified version of HASM is that it is theoretically perfect as it considers the third equation of the surface theory which reflects the local warping of the surface. The modified HASM may be useful with a wide range of spatial interpolation as it would no longer rely on other interpolation methods.

关键词： HASM spatial interpolation initial value sensitivity accuracy temperature

HASM quantum machine learning

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Science China Earth Sciences 2023年第9期66卷 1937-1945页

作者： tianxiang yue Chenchen WU Yi LIU Zhengping DU Na ZHAO Yimeng JIAO Zhe XU Wenjiao SHI State Key Laboratory of Resources and Environment Information System Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Yanqi Lake Beijing Institute of Mathematical Sciences and Applications Beijing 101408China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101499China College of Land Resources and Environment Jiangxi Agricultural UniversityNanchang 330045China

The miniaturization of transistors led to advances in computers mainly to speed up their *** miniaturization has approached its fundamental ***,many practices require better computational resources than the capabilities of existing ***,the development of quantum computing brings light to solve this *** briefly review the history of quantum computing and highlight some of its advanced *** on current studies,the Quantum Computing Advantage(QCA)seems *** challenge is how to actualize the practical quantum advantage(PQA).It is clear that machine learning can help with this *** method used for high accuracy surface modelling(HASM)incorporates reinforced machine *** can be transformed into a large sparse linear system and combined with the Harrow-Hassidim-Lloyd(HHL)quantum algorithm to support quantum machine *** has been successfully used with classical computers to conduct spatial interpolation,upscaling,downscaling,data fusion and model-data assimilation of ecoenvironmental ***,a training experiment on a supercomputer indicates that our HASM-HHL quantum computing approach has a similar accuracy to classical HASM and can realize exponential acceleration over the classical algorithms.A universal platform for hybrid classical-quantum computing would be an obvious next step along with further work to improve the approach because of the many known limitations of the HHL *** addition,HASM quantum machine learning might be improved by:(1)considerably reducing the number of gates required for operating HASM-HHL;(2)evaluating cost and benchmark problems of quantum machine learning;(3)comparing the performance of the quantum and classical algorithms to clarify their advantages and disadvantages in terms of accuracy and computational speed;and(4)the algorithms would be added to a cloud platform to support applications and gather active feedback from users

关键词： Quantum computing Machine learning Eco-environmental surface High accuracy surface modelling Quantum computational advantage Practical quantum advantage