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Timely monitoring of soil water-salt dynamics within cropland by hybrid spectral unmixing and machine learning models

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International Soil and Water Conservation Research 2024年第3期12卷 726-740页

作者： Ruiqi Du Junying Chen Youzhen Xiang Ru Xiang Xizhen Yang Tianyang Wang Yujie He Yuxiao Wu haoyuan yin Zhitao Zhang yinwen Chen College of Water Resources and Architectural Engineering Northwest A&F UniversityYanglingShanxi712100China College of Language and Culture Northwest A&F UniversityYanglingShanxi712100China

Soil salinization and water scarcity are main restrictive factors for irrigated agriculture development in arid *** dynamics of soil water and salt content is an important antecedent in remediating salinized soils and optimizing irrigation *** studies mostly used remote sensing technologies to individually monitor water or salt content dynamics in agricultural *** ability to asses different levels of crop water and salt management has been less ***,how to extract effective diagnostic features from remote sensing images derived spectral information is crucial for accurately estimating soil water and salt *** this study,Linear spectral unmixing method(LSU)was used to obtain the contribution of soil water and salt to each band spectrum(abundance),and endmember spectra from Sentinel-2 *** spectral indices and selecting optimal spectal combination were individually based on soil water and salt endmember *** estimation models were constructed using six machine learning algorithms:BP Neural Network(BPNN),Support Vector Regression(SVR),Partial Least Squares Regression(PLSR),Random Forest Regression(RFR),Gradient Boost Regression Tree(GBRT),and eXtreme Gradient Boosting tree(XGBoost).The results showed that the spectral indices calculated from endmember spectra were able to effectively characterize the response of crop spectral properties to soil water and salt,which circumvent spectral ambiguity induced by water-salt *** spectral index was a reliable indicator for estimating water and salt content,with determination coefficients(R2)being 0.55 and 0.57,*** to other models,LSU-XGBoost model achieved the best *** model properly reflected the process of soil water-salt dynamics in farmland during crop growth *** study provided new methods and ideas for soil water-salt estimation in dry irrigated agricultural areas,and provided decision support for gove

关键词： XGBoost Sentinel-2 Spectral unmixing Soil water Soil salt Irrigation area

A rationally designed CD19 monoclonal antibody-triptolide conjugate for the treatment of systemic lupus erythematosus

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Acta Pharmaceutica Sinica B 2024年第10期14卷 4560-4576页

作者： Lai Wang haoyuan yin Jiao Jiang Qilin Li Changxing Gao Wenrui Li Bo Zhang Yue Xin Hongyang Li Ming Zhao Qianjin Lu Hospital for Skin Diseases Institute of DermatologyChinese Academy of Medical Sciences and Peking Union Medical CollegeNanjing 210042China Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases Chinese Academy of Medical SciencesNanjing 210042China Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs Nanjing 210042China Hunan Key Laboratory of Medical Epigenomics the Second Xiangya HospitalCentral South UniversityChangsha 410011China

Tripterygium wilfordii Hook F(TWHF)is a traditional Chinese medicine widely used in the treatment of systemic lupus erythematosus(SLE),with triptolide(TP)as its main active ***,its side effects also induced by TP,especially hepatotoxicity and reproductive toxicity,largely limit its application in a subset of *** antibodies(mAbs)developed for the treatment of SLE that deplete B cells by targeting B cell-expressing antigens,such as CD19,have failed in clinical trials,partly due to their poor efficacy in consuming B ***,we report the development of a rationally designed antibody‒drug conjugate(ADC),CD19 mAb-TP conjugate,to alleviate the side effects of TWHF and simultaneously improve the therapeutic efficacy of CD19 *** CD19 mAb-TP conjugate,which was named ADC-TP,selectively depleted B cell subsets both in vitro and in vivo and effectively alleviated disease symptoms in mouse lupus models with enhanced therapeutic efficacy than CD19 mAb and fewer side effects than *** present study proposes a CD19 mAb‒TP conjugate strategy to mitigate the toxicity of TWHF while also enhancing the therapeutical efficacy of CD19 mAbs for the treatment of SLE,providing a feasible method for improving the current agents used for treating SLE.

关键词： Systemic lupus erythematosus Triptolide CD19 Antibody‒drug conjugate B cells Reproductive toxicity Synergistic effect Targeted therapy

Multi-scenario simulation of land use change and its impact on ecosystem services in the northeastern edge of the Qinghai-Xizang Plateau,China

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Journal of Arid Land 2025年第2期17卷 145-166页

作者： ZHANG Xuebin LIU Yanni yin Junfeng SHI Peiji FENG haoyuan SHI Jing College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Faculty of Geographic Sciences Beijing Normal UniversityBeijing 100875China State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems College of EcologyLanzhou UniversityLanzhou 730000China

The Qinghai-Xizang Plateau(QXP)serves as a crucial ecological barrier in China and Asia,exerting profound influences on global climate and biodiversity *** Tibetan Autonomous Prefecture(hereinafter referred as Gannan Prefecture),located on the northeastern edge of the QXP,represents a fragile alpine ecosystem in which land use change significantly impacts ecosystem services(ESs).This study established a comprehensive framework,utilizing the Patch-generating Land-Use Simulation(PLUS)model coupled with the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to predict land use patterns under the natural development scenario,cultivated land protection scenario,and ecological protection scenario for Gannan Prefecture by 2030 and evaluated four critical ESs:habitat quality(HQ),water yield(WY),soil retention(SR),and carbon storage(CS).The primary aim is to elucidate the impacts of dynamic land use change on *** results revealed that,from 2000 to 2020,HQ exhibited minimal variation,whereas CS experienced a slight ***,WY and SR showed significant *** the natural development scenario,construction land was projected to increase by 4247.74 hm^(2),primarily at the expense of forest *** cultivated land protection scenario anticipated an increase in farmland by 2634.36 hm^(2),which was crucial for maintaining food *** ecological protection scenario predicted a notable expansion of forest land,accompanied by a restrained development rate of construction *** ecological protection scenario also showed an increase in the ecosystem service index(ESI),encompassing 26.07%of the *** land and grassland emerged as the primary contributors to ESs,while construction land substantially impacted *** bodies exhibited minimal contribution to *** study enhanced the understanding of land use change impacts on ESs in fragile and high-altitude ecosystems,offering essential theoretical framework

关键词： PLUS-InVEST model ecosystem service habitat quality water yield soil retention carbon storage Qinghai-Xizang Plateau

免疫检查点抑制剂的免疫相关不良事件预测生物标志物研究进展

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肿瘤防治研究 2021年第4期48卷 418-423页

作者：李颖尹皓原潘丽冯磊昆明医科大学附属第六医院检验科玉溪653100

近年来,以免疫检查点为靶点的肿瘤免疫疗法因疗效显著而备受关注。然而随着免疫检查点抑制剂(ICIs)的推广应用,其相关不良事件(irAEs)的报道也越来越多。irAEs使接受ICIs治疗的肿瘤患者承担着额外的致命风险,限制着ICIs的使用。为帮助... 详细信息

近年来,以免疫检查点为靶点的肿瘤免疫疗法因疗效显著而备受关注。然而随着免疫检查点抑制剂(ICIs)的推广应用,其相关不良事件(irAEs)的报道也越来越多。irAEs使接受ICIs治疗的肿瘤患者承担着额外的致命风险,限制着ICIs的使用。为帮助患者主动预防irAEs,研究具有irAEs预测价值的生物标志物意义重大。本文将从血清学、遗传学、微生物学等多个层面对irAEs有预测价值的生物标志物的研究进展作一综述。

关键词：免疫检查点抑制剂免疫相关不良事件生物标志物

基于Landsat8与Sentinel-1遥感图像融合的土壤含水率反演模型

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农业机械学报 2024年第2期55卷 208-219页

作者：陈俊英项茹贺玉洁吴雨箫殷皓原张智韬西北农林科技大学水利与建筑工程学院陕西杨凌712100 西北农林科技大学旱区农业水土工程教育部重点实验室陕西杨凌712100

针对当前运用单一光学卫星反演土壤含水率时易受到云的影响,单一SAR卫星反演土壤含水率时易受到地表粗糙度和植被影响的问题,以内蒙古河套灌区沙壕渠为研究区域,以4个深度的土壤含水率为研究对象,分别采用主成分分析(PCA)、施密特正交变... 详细信息

针对当前运用单一光学卫星反演土壤含水率时易受到云的影响,单一SAR卫星反演土壤含水率时易受到地表粗糙度和植被影响的问题,以内蒙古河套灌区沙壕渠为研究区域,以4个深度的土壤含水率为研究对象,分别采用主成分分析(PCA)、施密特正交变换(GS)融合Landsat8和Sentinel-1图像以减少云、植被、土壤粗糙度的影响,并对融合后的图像质量进行评价,然后用融合图像的灰度构建1134种遥感指数,基于相关系数分析、变量投影重要性分析、灰色关联分析3种变量筛选方法与BP神经网络(BP)、极限学习机(ELM)、随机森林(RF)、支持向量机(SVM)4种机器学习算法的耦合模型反演沙壕渠土壤含水率。研究结果表明:经PCA、GS融合后的融合图像可同时保持Sentinel-1和Landsat8图像的优势,并成功定量反演土壤含水率。基于融合图像构建的三维指数普遍比二维指数对土壤含水率更敏感。在表层土壤含水率反演中,基于GS融合的VIP-ELM模型精度最高(决定系数R2=0.66,均方根误差(RMSE)为1.35%)。将GS融合的VIP-ELM模型应用于其他土壤深度含水率的反演后发现,20~40 cm反演精度最高(R2=0.79,RMSE为0.94%),其次是0~10 cm、40~60 cm、10~20 cm。该研究可为多源卫星图像融合反演土壤含水率提供参考。

关键词：土壤含水率卫星图像融合机器学习耦合模型

基于Sentinel-1/2改进极化指数和纹理特征的土壤含盐量反演模型

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农业机械学报 2024年第1期55卷 175-185页

作者：张智韬贺玉洁殷皓原项茹陈俊英杜瑞麒西北农林科技大学水利与建筑工程学院陕西杨凌712100 西北农林科技大学旱区农业水土工程教育部重点实验室陕西杨凌712100

目前Sentinel-1/2协同反演植被土壤含盐量的研究大多是基于Sentinel-2光谱信息和Sentinel-1后向散射系数,没有考虑Sentinel-2光谱信息容易受土壤亮度等信息影响,Sentinel-1后向散射系数容易受土壤粗糙度和水分影响。为进一步提高Sentine... 详细信息

目前Sentinel-1/2协同反演植被土壤含盐量的研究大多是基于Sentinel-2光谱信息和Sentinel-1后向散射系数,没有考虑Sentinel-2光谱信息容易受土壤亮度等信息影响,Sentinel-1后向散射系数容易受土壤粗糙度和水分影响。为进一步提高Sentinel-1/2协同反演植被土壤含盐量的精度,用水云模型对雷达卫星后向散射系数进行校正,消除植被影响;然后协同Sentinel-2纹理特征,基于VIP、OOB、PCA 3种变量筛选和RF、ELM、Cubist 3种机器学习回归模型构建植被土壤含盐量反演模型。研究结果表明:经过水云模型去除植被影响后的雷达后向散射系数及其极化组合指数与土壤含盐量的相关性有一定程度的提高。不同变量选择方法与不同机器学习方法耦合模型在反演土壤含盐量中,OOB变量筛选方法与RF、ELM和Cubist 3种机器学习方法的耦合模型精度最佳,建模集和验证集的R2都在0.750以上,且验证集的RMSE和MAE均最小;其中OOB-Cubist耦合模型精度最高,且R_(v)^(2)/R_(c)^(2)为0.955,具有良好的鲁棒性。研究可为机器学习协同物理模型、光学卫星协同雷达卫星在土壤含盐量反演中的进一步应用提供思路。

关键词：土壤含盐量 Sentinel-1/2 纹理特征水云模型机器学习改进极化指数

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Sentinel-2多光谱卫星遥感反演植被覆盖下的土壤盐分变化

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农业工程学报 2021年第17期37卷 107-115页

作者：杜瑞麒陈俊英张智韬徐洋洋张兴殷皓原杨宁西北农林科技大学水利与建筑工程学院杨凌712100 西北农林科技大学旱区农业水土工程教育部重点实验室杨凌712100

为克服植被覆盖条件下土壤盐分含量与光谱反射率之间相关性较差所带来反演精度较低的问题,该研究以内蒙古河套灌区沙壕渠灌域为研究区域,利用Sentinel-2卫星同步获取光谱数据,通过构建以归一化植被指数(Normalized Difference Vegetatio... 详细信息

为克服植被覆盖条件下土壤盐分含量与光谱反射率之间相关性较差所带来反演精度较低的问题,该研究以内蒙古河套灌区沙壕渠灌域为研究区域,利用Sentinel-2卫星同步获取光谱数据,通过构建以归一化植被指数(Normalized Difference Vegetation Index,NDVI)为分支标准的盐分深度决策树确定反演土壤盐分含量的最佳深度,然后构建以NDVI和表层土壤含水率为分支标准的类别决策树,将土壤样本划分为不同类别,以此分别构建土壤盐分反演模型,并评估反演效果。研究结果表明,决策树能增强光谱反射率对土壤盐分含量的敏感性,基于随机森林(Random Forest,RF)的盐分反演模型可取得理想的反演效果,决定系数为0.70,均方根误差为0.25%,相对分布误差为0.35,相对分析误差为1.67。土壤盐分含量反演模型能较好地反演表层(40~60 cm)土壤盐分含量,在反演中层(20~40 cm)土壤盐分含量上存在一定局限。当地表有植被覆盖时,利用决策树可有效地提高土壤盐分含量的反演精度(与未考虑决策树相比,决定系数和相对分析误差分别提高0.32和0.80)。研究结果可为监测灌区内作物生育期间土壤盐分含量的动态变化提供方法参考。

关键词：土壤盐分遥感 Sentinel-2卫星土壤水分河套灌区反演

基于Sentinel-2卫星数据的灌区农田土壤水盐协同反演

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农业工程学报 2023年第16期39卷 111-121页

作者：贺玉洁张智韬巴亚岚杜瑞麒殷皓原项茹吴雨箫西北农林科技大学水利与建筑工程学院杨凌712100 西北农林科技大学旱区农业水土工程教育部重点实验室杨凌712100

土壤含水量(soil water content, SWC)和土壤含盐量(soil salt content, SSC)是影响作物生长和农业生产力的重要因素。光学卫星图像已成为SWC和SSC估计的主要数据源。然而,在SWC或SSC变化较大地区,土壤水分和盐分会影响对方对光谱反射... 详细信息

土壤含水量(soil water content, SWC)和土壤含盐量(soil salt content, SSC)是影响作物生长和农业生产力的重要因素。光学卫星图像已成为SWC和SSC估计的主要数据源。然而,在SWC或SSC变化较大地区,土壤水分和盐分会影响对方对光谱反射率的响应,使得SSC和SWC的反演精度较差。对此,该研究提出了一个半解析性的反射率模型—RVS模型,来模拟植被光谱反射率(R_(v))对作物根区土壤含水量和含盐量的响应;并通过构建的RVS模型,对植被覆盖区域的土壤含水量和土壤含盐量进行同步监测。研究表明:RVS模型在反演研究区土壤含盐量和含水量时,精度较为可靠(水分:决定系数R^(2)为0.63~0.74,均方根误差为0.017~0.028;盐分:决定系数R^(2)为0.68~0.75,均方根误差为0.052 5~0.061 7)。在作物生长过程中,植被光谱反射率对深层土壤的含水量和含盐量的响应比对浅层土壤的含水量和含盐量的响应更加明显,而且随着作物的生长,影响光谱反射率的主导因素从土壤水分慢慢转向土壤盐分和水盐相互作用。该研究在一定程度上揭示了土壤水分、盐分、水盐交互作用对作物光谱反射率的干扰过程,实现土壤水分和盐分的同步监测,对实现区域尺度上土壤含盐量和含水量的精准监测具有一定的意义。

关键词：土壤含水量含盐量灌溉农田 Sentinel-2卫星光谱-空间

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重症肺炎患者外周血Treg/Th17及其相关细胞因子与肠道菌群的相关性

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标记免疫分析与临床 2021年第2期28卷 318-321页

作者：李轶峰刘超尹皓原玉溪市人民医院心胸外科云南玉溪653100

目的探讨重症肺炎患者外周血中Treg/Th17及其相关细胞因子与肠道菌群的相关性。方法选取我科收治的重症肺炎患者72例为研究组,正常对照者60例。比较其外周血Treg/Th17及其相关细胞因子、肠道菌群的变化情况,并分析其相关性。结果与对照... 详细信息

目的探讨重症肺炎患者外周血中Treg/Th17及其相关细胞因子与肠道菌群的相关性。方法选取我科收治的重症肺炎患者72例为研究组,正常对照者60例。比较其外周血Treg/Th17及其相关细胞因子、肠道菌群的变化情况,并分析其相关性。结果与对照组相比,研究组患者外周血中的Th17频率及Il-17水平较对照组显著升高,而Treg频率、Il-10和TGF-β水平显著降低;研究组厚壁菌门占比显著低于对照组,而互养菌门、放线菌门及梭杆菌门占比则显著高于对照组;研究组双歧杆菌属、瘤胃球菌属、粪球菌属、假丁酸弧菌属及毛螺菌属占比显著低于对照组,而葡萄球菌属及梭杆菌属占比则升高;重症肺炎外周血Treg频率、IL-10及TGF-β水平均与厚壁菌门、双歧杆菌属及瘤胃球菌属成正相关,而与葡萄球菌属及梭杆菌属成负相关,而Th17及IL-17则相反。结论重症肺炎患者外周血Treg/Th17及其相关细胞因子与肠道菌群间存在一定的相关性。

关键词：重症肺炎细胞因子 Th17 Treg 肠道菌群