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Combining the critical nitrogen concentration and machine learning algorithms to estimate nitrogen deficiency in rice from UAV hyperspectral data

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Journal of Integrative Agriculture 2023年第4期22卷 1216-1229页

作者： yu Feng-hua BAI Ju-chi jin zhong-yu GUO zhong-hui YANG Jia-xin CHEN Chun-ling School of Information and Electrical Engineering Shenyang Agricultural UniversityShenyang 110866P.R.China Key Laboratory of Intelligent Agriculture in Liaoning Province Shenyang 110866P.R.China

Rapid and large area acquisition of nitrogen(N)deficiency status is important for achieving the optimal fertilization of *** existing studies,however,focus on the use of unmanned aerial vehicle(UAV)remote sensing to diagnose N nutrition in rice,while there are fewer studies on the quantitative description of the degree of N deficiency in rice,and the effects of the critical N concentration on the spectral changes in rice have rarely been ***,based on the canopy spectral data obtained by remotely-sensed UAV hyperspectral images,the N content in rice was obtained through field *** construction method of the rice curve for the northeastern critical N concentration was studied,and on this basis,N deficiency was *** the spectrum of the critical N concentration state as the standard spectrum,the spectral reflectivity data were transformed by the ratios and differences,and the feature extraction of the spectral data was carried out by the successive projections algorithm(SPA).Finally,by taking the characteristic band as the input variable and N deficiency as the output variable,a set of multivariate linear regression(MLR),long short-term memory(LSTM)inversion models based on extreme learning machine(ELM),and the nondominated sorting genetic algorithmⅢextreme learning machine(NSGA-Ⅲ-ELM)were *** results showed two key aspects of this system:1)The correlation between the N deficiency data and original spectrum was poor,but the correlation between the N deficiency data and N deficiency could be improved by a difference change and ratio transformation;2)The inversion results based on the ratio spectrum and NSGA-Ⅲ-ELM algorithm were the best,as the R2values of the training set and validation set were 0.852 and 0.810,and the root mean square error(RMSE)values were 0.291 and 0.308,*** the perspective of the spectral data,the inversion accuracy of the ratio spectrum was better than the accuracy of the original s

关键词： UAV hyperspectral nitrogen deficiency critical nitrogen concentration NSGA-Ⅲ

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Pollinator-dependent evolution of floral trait combinations in an orchid herb

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Journal of Plant Ecology 2020年第4期13卷 450-459页

作者： yun Wu Xu-yu Duan Yong Xiang Shao-Bin Weng jin-yu zhong jing Li Qing-Jun Li School of Civil Engineering Architecture and EnvironmentXihua UniversityChengdu 610039China yunnan Key Laboratory of Plant Reproductive Adaption and Evolutionary Ecology Kunming 650091China Laboratory of Ecology and Evolutionary Biology Yunnan UniversityKunming 650091China South-East Tibetan Plateau Station for Integrated Observation and Research of Alpine Environment Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Landscape Architecture Sichuan Agricultural UniversityChengdu 611130China

Aims As one of the most important agents driving floral evolution,pollinators shape the diversity of flowers in ***,most previous studies have only quantified pollinators driving the evolution of a single floral trait,and experimental estimates of the potential role of pollinators in shaping the evolution of floral trait associations are relatively *** We experimentally identified and estimated the pollinator-mediated directional and correlational selection on single floral traits and trait combinations across 2 years in an orchid species,Spiranthes *** Findings Pollinators mediated directional selection for an earlier flowering start date and larger corolla *** mediated positive correlational selection on the combinations of floral display traits and negative correlational selection on the combinations of flowering phenology and floral display *** addition,the strength of selection differed over *** results highlight the potential role of pollinators in driving the evolution of floral trait combinations and suggest that it is necessary to consider floral character functional associations when seeking to understand and predict the evolutionary trajectory of flowers in angiosperms.

关键词： directional and correlational selection floral evolution pollinator-mediated selection Spiranthes sinensis trait combinations

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Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： Ming‑yuan yu jing Wu Guang Yin Fan‑Zhen Jiao zhong‑Zhen yu jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

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Prognostic model for esophagogastric variceal rebleeding after endoscopic treatment in liver cirrhosis: A Chinese multicenter study

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World Journal of Gastroenterology 2025年第2期31卷 85-101页

作者： Jun-Yi Zhan Jie Chen jin-zhong yu Fei-Peng Xu Fei-Fei Xing De-Xin Wang Ming-Yan Yang Feng Xing Jian Wang Yong-Ping Mu Cell Biology Laboratory Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Institute of Liver Diseases Shanghai Academy of Chinese MedicineShanghai 201203China Clinical Key Laboratory of Traditional Chinese Medicine of Shanghai Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Key Laboratory of Liver and Kidney Disease of the Ministry of Education Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Gastroenterology and Hepatology Zhongshan Hospital Affiliated to Fudan UniversityShanghai 200032China Shanghai Institute of Liver Disease Fudan UniversityShanghai 200032China Evidence-Based Medicine Center Fudan UniversityShanghai 200032China Department of Gastrointestinal Endoscopy Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Hepatology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China

BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and *** its clinical importance,recognized prognostic models that can effectively predict esophagogastric variceal rebleeding in patients with liver cirrhosis are *** To construct and externally validate a reliable prognostic model for predicting the occurrence of esophagogastric variceal *** This study included 477 EGVB patients across 2 cohorts:The derivation cohort(n=322)and the validation cohort(n=155).The primary outcome was rebleeding events within 1 *** least absolute shrinkage and selection operator was applied for predictor selection,and multivariate Cox regression analysis was used to construct the prognostic *** validation was performed with bootstrap *** assessed the discrimination,calibration and accuracy of the model,and performed patient risk *** Six predictors,including albumin and aspartate aminotransferase concentrations,white blood cell count,and the presence of ascites,portal vein thrombosis,and bleeding signs,were selected for the rebleeding event prediction following endoscopic treatment(REPET)*** predicting rebleeding within 1 year,the REPET model ex-hibited a concordance index of 0.775 and a Brier score of 0.143 in the derivation cohort,alongside 0.862 and 0.127 in the validation ***,the REPET model revealed a significant difference in rebleeding rates(P<0.01)between low-risk patients and intermediate-to high-risk patients in both *** We constructed and validated a new prognostic model for variceal rebleeding with excellent predictive per-formance,which will improve the clinical management of rebleeding in EGVB patients.

关键词： Esophagogastric variceal bleeding Variceal rebleeding Liver cirrhosis Prognostic model Risk stratification Secondary prophylaxis

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Proteomic profiling of fetal esophageal epithelium, esophageal cancer, and tumor-adjacent esophageal epithelium and immunohistochemical characterization of a representative differential protein, PRX6

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World Journal of Gastroenterology 2017年第8期23卷 1434-1442页

作者： Jun-Hui Guo Guo-Lan Xing Xin-Hui Fang Hui-Fang Wu Bo Zhang jin-zhong yu Zong-Min Fan Li-Dong Wang Henan Province Hospital of TCM The Second Affiliated Hospital of Henan University of Chinese Medicine Henan Key Lab For Esophageal Cancer Res The First Affiliated Hospital of Zhengzhou University Henan Province People’s Hospital The Second Affiliated Hospital of Zhengzhou University

AIM To understand the molecular mechanism of esophageal cancer development and provide molecular markers for screening high-risk populations and early diagnosis. METHODS Two-dimensional electrophoresis combined with mass spectrometry were adopted to screen differentially expressed proteins in nine cases of fetal esophageal epithelium, eight cases of esophageal cancer, and eight cases of tumor-adjacent normal esophageal epithelium collected from fetuses of different gestational age, or esophageal cancer patients from a high-risk area of esophageal cancer in China. Immunohistochemistry(avidin-biotin-horseradish peroxidase complex method) was used to detect the expression of peroxiredoxin(PRX)6 in 91 cases of esophageal cancer, tumoradjacent normal esophageal tissue, basal cell hyperplasia, dysplasia, and carcinoma in situ, as well as 65 cases of esophageal epithelium from fetuses at a gestational age of 3-9 *** After peptide mass fingerprint analysis and search of protein databases, 21 differential proteins were identified; some of which represent a protein isoform. Varying degrees of expression of PRX6 protein, which was localized mainly in the cytoplasm, were detected in adult and fetal normal esophageal tissues, precancerous lesions, and esophageal cancer. With the progression of esophageal lesions, PRX6 protein expression showed a declining trend(P < 0.05). In fetal epithelium from fetuses at gestational age 3-6 mo, PRX6 protein expression showed a declining trend with age(P < 0.05). PRX6 protein expression was significantly higher in well-differentiated esophageal cancer tissues than in poorly differentiated esophageal cancer tissues(P < 0.05).CONCLUSION Development and progression of esophageal cancer result from interactions of genetic changes(accumulation or superposition). PRX6 protein is associated with fetal esophageal development and cancer differentiation.

关键词： Fetal esophageal epithelium Esophageal squamous cell carcinoma Tumor-adjacent esophageal epithelium Proteomics

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao yuan-yuan Zhu Liang-jin Xu yu-Wu zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

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北方寒地水稻叶片磷素含量高光谱反演方法研究

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光谱学与光谱分析 2023年第5期43卷 1442-1449页

作者：杨柳郭忠辉金忠煜白驹驰于丰华许童羽沈阳农业大学信息与电气工程学院辽宁沈阳110866 辽宁省农业信息化工程技术研究中心辽宁沈阳110866

为了快速、准确的检测北方寒地水稻叶片的磷素含量,分析水稻的长势情况,为精准施肥以及稻田的科学管理提供依据,以北方寒地水稻为研究对象,以小区实验为基础,使用海洋光学HR 2000+光谱仪获取水稻叶片高光谱反射率数据,采用钒钼黄比色法... 详细信息

为了快速、准确的检测北方寒地水稻叶片的磷素含量,分析水稻的长势情况,为精准施肥以及稻田的科学管理提供依据,以北方寒地水稻为研究对象,以小区实验为基础,使用海洋光学HR 2000+光谱仪获取水稻叶片高光谱反射率数据,采用钒钼黄比色法对水稻叶片磷素含量进行测定。采用SG平滑与多元散射校正(MSC)两种方法对水稻叶片高光谱数据进行预处理,并将预处理后的光谱数据使用连续投影法(SPA)与无信息变量消除法(UVE)两种算法进行特征选择。采用SPA算法筛选得到的特征共有11个,其中位于可见光波段处的有6个,分别为411、 420、 428、 442、 467和689 nm;近红外波段处有5个,分别为797、 850、 866、 965和976 nm;UVE算法筛选得到的特征共47个,均位于可见光波段范围内,分布在405~603 nm之间。分别将这两种方法筛选出的特征波段的反射率作为输入,构建极限学习机(ELM), BP神经网络以及狼群算法优化的BP神经网络(WPA-BP)三种水稻叶片磷素含量反演模型并加以分析。结果表明:以UVE算法筛选的特征反射率为输入量构建的三种模型的验证集R^(2)在0.705 2~0.724 5之间,RMSE在0.017 4~0.020 4之间;在相同的反演模型的条件下,使用SPA算法筛选的特征反射率为输入量构建的模型预测效果更好,三种模型的验证集R^(2)在0.726 4~0.829 3之间,RMSE在0.018 0~0.021 1之间;另外,在利用这两种算法筛选到的特征进行建模时,对比三种模型的预测结果发现,经过狼群算法优化后的BP神经网络模型的精度明显高于极限学习机和BP神经网络,其验证集的决定系数R^(2)为0.803 4, RMSE为0.018 0。鉴于此,结合连续投影算法和狼群算法优化后的BP神经网络模型在北方寒地水稻叶片磷素含量高光谱反演中具有一定的优势,可作为水稻叶片磷素含量的检测以及精准定量施肥的参考和借鉴。

关键词：水稻高光谱数据磷素含量狼群算法反演模型

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水稻分蘖期无人机高光谱影像混合像元特征分析与分解

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光谱学与光谱分析 2022年第3期42卷 947-953页

作者：于丰华赵丹郭忠辉金忠煜郭爽陈春玲许童羽沈阳农业大学信息与电气工程学院辽宁沈阳110866 辽宁省农业信息化工程技术研究中心辽宁沈阳110866

开展水稻无人机高光谱解混,获取水稻植株的高光谱反射率信息,对于提高水稻理化参量的反演模型精度具有重要意义。目前大多基于高光谱遥感影像自身数据进行解混,运用算法模型进行高光谱数据解混,将高光谱图像和可见光图像进行优势互补,... 详细信息

开展水稻无人机高光谱解混,获取水稻植株的高光谱反射率信息,对于提高水稻理化参量的反演模型精度具有重要意义。目前大多基于高光谱遥感影像自身数据进行解混,运用算法模型进行高光谱数据解混,将高光谱图像和可见光图像进行优势互补,提出一种基于无人机高清影像与高光谱遥感影像融合的稻田无人机高光谱解混方法,解决单一数据局限性问题,增强光谱数据对地物的描述能力。为了更好的计算端元丰度,将同一目标区的高清数码正射影像与无人机高光谱遥感影像利用经纬度信息进行空间配准,使得不同传感器获得的图片在几何位置上对齐,通过SVM分类器的监督分类方法对可见光的数码正射影像进行地物分类,利用地物分类的结果对应高光谱的一个像元,从而得到一个像元内的端元丰度。设相邻区域内的水体端元是相同的,利用线性解混模型(LSMM)对相邻区域的混合像元进行解混,最终获取水稻高光谱反射率信息。结果表明对两种图片进行空间配准丰富了数据源信息,有利于像元的端元丰度计算,其中水稻端元丰度在70%以上解混效果最好,丰度在50%以上解混效果一般,丰度在30%以下解混效果较差;选择监督分类方法进行地物分类,精度达到99.5%,面向对象方法分类精度为98.2%,监督分类方法优于面向对象分类方法;最终得到的混合像元分解反射率高于原混合像元反射率,减少了水体混合部分对光谱数据的影响,使得分解后水稻的光谱反射率更加准确,为水稻理化参量无人机成像高光谱遥感反演提供更加准确的科学依据。

关键词：高光谱无人机端元提取水稻混合像元

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海森伯与中国物理学界

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物理 2010年第2期39卷 136-141页

作者：金忠玉王士平首都师范大学物理系北京100048

著名物理学家海森伯曾于1929年访华,旋即被聘为中央研究院物理所名誉研究员,成为中国近代物理学史上第一个获此荣誉的外籍学者.文章对他来华的具体时间作出推断,述及其与早期中国物理学界某些人士的因缘.

关键词：物理学史海森伯中国物理学界

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Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie Jia-Lin Li Ling Gong Xiang-Li zhong Hong-Jia Song jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

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