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Estimation of Sunflower Seed Yield Using Partial Least Squares Regression and Artificial Neural Network Models

Pedosphere 2018年第5期28卷 764-774页

作者： ZENG Wenzhi XU Chi Gang ZHAO WU Jingwei HUANG Jiesheng State Key Laboratory of Water Resources and Hydropower Engineering science Wuhan University (China) crop science Group Institute of Crop Science and Resource Conservation University of Bonn Katzenburgweg 5 Bonn 53115(Germany)

Statistical models can efficiently establish the relationships between crop growth and environmental conditions while explicitly quantifying uncertainties. This study aimed to test the efficiency of statistical models established using partial least squares regression(PLSR) and artificial neural network(ANN) in predicting seed yields of sunflower(Helianthus annuus). Two-year field trial data on sunflower growth under different salinity levels and nitrogen(N) application rates in the Yichang Experimental Station in Hetao Irrigation District, Inner Mongolia, China, were used to calibrate and validate the statistical models. The variable importance in projection score was calculated in order to select the sensitive crop indices for seed yield prediction. We found that when the most sensitive indices were used as inputs for seed yield estimation, the PLSR could attain a comparable accuracy(root mean square error(RMSE) = 0.93 t ha-1, coefficient of determination(R^2) = 0.69) to that when using all measured indices(RMSE = 0.81 t ha-1,R^2= 0.77). The ANN model outperformed the PLSR for yield prediction with different combinations of inputs of both microplots and field data. The results indicated that sunflower seed yield could be reasonably estimated by using a small number of crop characteristic indices under complex environmental conditions and management options(e.g., saline soils and N application). Since leaf area index and plant height were found to be the most sensitive crop indices for sunflower seed yield prediction, remotely sensed data and the ANN model may be joined for regional crop yield simulation.

关键词： leaf area index microplot experiment plant height remote sensing salinization variable importance in projection score

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Protective and defensive roles of non-glandular trichomes against multiple stresses:structure-function coordination

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Journal of Forestry Research 2020年第1期31卷 1-12页

作者： George Karabourniotis Georgios Liakopoulos Dimosthenis Nikolopoulos Panagiota Bresta Laboratory of Plant Physiology Department of Crop ScienceAgricultural University of Athens

As superficial structures,non-glandular trichomes,protect plant organs against multiple biotic and abiotic *** protective and defensive roles of these epidermal appendages are crucial to developing organs and can be attributed to the excellent combination of suitable structural traits and chemical reinforcement in the form of phenolic compounds,primarily fl *** the formation of trichomes and the accumulation of phenolics are interrelated at the molecular *** the early stages of development,non-glandular trichomes show strong morphological similarities to glandular ones such as the balloon-like apical cells with numerous *** later developmental stages,and during secondary wall thickening,phenolics are transferred to the cell walls of the *** to the diff use deposition of phenolics in the cell walls,trichomes provide protection against UV-B radiation by behaving as optical fi lters,screening out wavelengths that could damage sensitive *** from strong visible radiation is also aff orded by increased surface light refl ***,the mixtures of trichome phenolics represent a superfi-cial chemical barrier that provides protection against biotic stress factors such as herbivores and *** the cells of some trichomes die at maturity,they can modulate their quantitative and qualitative characteristics during development,depending on the prevailing conditions of the external biotic or abiotic *** fact,the structure and chemical constituents of trichomes may change due to the particular light regime,herbivore damage,wounding,water stress,salinity and the presence of heavy ***,trichomes represent dynamic protective structures that may greatly aff ect the outcome of many plant–environment interactions.

关键词： Non-glandular trichomes Phenolics Flavonoids Protection Defence Biotic stress Abiotic stress

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Chemical Empiricism 2.0 at Age of Big Data: Large-scale Prediction of Reaction Pathways Based on Bond Dissociation Energies

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Shi-lu Chen Key Laboratory of cluster science of Ministry of Education School of Chemistry Beijing Institute of Technology Beijing 100081 China

A programmable algorithm using bond dissociation energies has been proposed for the prediction of reaction pathways. It has been successfully applied to a gas-phase reaction of F2+CH3Cl, with the accurate revelation of the most favorable product CF4 and its corresponding reaction pathway. This acts as an inspiring example of chemical empiricism 2.0, and may open the door for the large-scale prediction of reaction pathways at the age of big data.

关键词： Big data Bond dissociation energy Reaction pathway Prediction

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Evaluation of selenium and carotenoid concentrations of 200 foxtail millet accessions from China and their correlations with agronomic performance

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Journal of Integrative Agriculture 2016年第7期15卷 1449-1457页

作者： LIU Min-xuan ZHANG Zong-wen REN Gui-xing ZHANG Qi WANG Yin-yue LU Ping Institute of crop science Chinese Academy of Agricultural Sciences Faculty of Life science Jilin Agricultural University

As selenium and carotenoids are essential micronutrients, the determination of their concentrations in different varieties is important in the breeding of foxtail milet （Setaria italicaL. ***.）. To identify selenium- and carotenoid-enriched foxtail milet varieties and to analyze correlations between trace elements and agronomic traits, we measured the selenium and carotenoid concentrations of 200 Chinese accessions by high-performance liquid chromatography and atomic lfuorescence spectrometry. Our analysis revealed that lutein concentration in 200 foxtail milet accessions folowed normal distribution and average was 3.1 μg g–1. The mean value of zeaxanthin concentration in 200 accessions was 8.6 μg g–1. Lutein and zeaxanthin concentrations were higher in the foxtail milet from Liaoning than in varieties from other locations, with averages of 10.0 and 3.5 μg g–1, respectively. The average measured selenium concentration was 100.3 μg kg–1. The highest average selenium concentration, 110.3 μg kg–1, was found in varieties from Shanxi. Varieties from Inner Mongolia had the lowest average selenium concentration, 84.7 μg kg–1, which was signiifcantly lower （P〈0.05） than that of Shanxi. Selenium con-centrations of 23 varieties were higher than 117.9 μg kg–1, accounting for 11.5% of the total, thereby were considered to be enriched in selenium. In addition, we identiifed 29 lutein-enriched varieties （〉4.27 μg g–1） and 30 zeaxanthin-enriched ones （〉12.63 μg g–1）, which corresponded to 14.5 and 15% of tested accessions, respectively. Correlation analysis revealed that selenium concentration was signiifcantly positively correlated with spikelet length （P〈0.01）, while zeaxanthin concentration was signiifcantly correlated with grass weight （P〈0.05） and spikelet length （P〈0.01）. No correlation was found between lutein concentration and agronomic characters, selenium content or zeaxanthin content. Our results should contribute substantialy to the selection of suitable varieties

关键词： foxtail milet varieties selenium carotenoids HPLC correlation analysis

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Isolation and Characterization of GmSTY1,a Novel Gene Encoding a Dual-Specificity Protein Kinase in Soybean（ Glycme max L.）

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Journal of Integrative Plant Biology 2006年第7期48卷 857-866页

作者： Zhao-Shi Xu You-Zhi Ma Xian-Guo Cheng Li-Xia Cao Lian-Cheng Li Ming Chen Key Laboratory of crop Genetics and Breeding Ministry of Agriculture Institute of Crop Science the Chinese Academy of Agricultural Sciences Beijing 100081 China

Phosphorylation of protein klnases has profound effects on their activity and interaction with other proteins. Tyroslne phosphorylation was reported to be involved in various physiological processes in plants; however, no typical receptor tyrosine kinase has been isolated from plants thus far. Dual-specificity kinases are potentially responsible for the phosphorylation of both tyrosine and serine/threonine of target proteins. A cDNA clone encoding a putative dual-specificity protein kinase was isolated by screening the cDNA GAL4 activation domain （AD） fusion library of soybean （Glycine max L.）, and its entire length was obtained using 5＇-rapid ampUflcatlon of cDNA ends. The predicted polypeptide of 330 amino acid residues, designated as GmSTY1, contains all 11 conserved subdomains, which share common characteristics with both the serine/ threonine and tyroslne protein klnases reported thus far. In addition, three potential N-linked glycosylation sites （NXS/T）, as well as phosphorylation motifs （SXXXS/T）, were observed, suggesting that GmSTY1 may be post-translationally modified. Furthermore, a potential N-myristoylation motif （MGARCSK） was found, suggesting that the GmSTY1 protein could associate with membranes in vivo. Southern blotting analysis revealed a single-copy of GmSTY1 in the genome. Northern blotting analysis showed that this gene was upregulated by drought and salt treatment in a time-dependent manner; however, exogenous abscisic acid （ABA） could not significantly affect the mRNA accumulation of GmSTY1. Interestingly, the transcript of this gene was remarkably downregulated by cold treatment during the early stages of the response, but upregulated later. These results Indicate that the protein kinase was possibly regulated by abiotic stresses in an ABA-independent pathway.

关键词： abiotic stress dual-specificity Glycine max , serine/threonine/tyrosine protein kinase.

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Tuning surface active oxygen of lanthanum oxide via partial dissolution and regrowth of crystallites

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Journal of Natural Gas Chemistry 2011年第5期20卷 483-486页

作者： Zhiming Gao, Huili Li Key Laboratory of cluster science, Ministry of Education of China Department of Chemistry, School of science, Beijing Institute of Technology, Beijing 100081, China Key Laboratory of cluster science Ministry of Education of China Department of Chemistry School of Science Beijing Institute of Technology Beijing 100081 China

A commercial lanthanum oxide was modified into X%-La2O3 samples via partial dissolution and regrowth of crystallites, wherein the X value denotes the weight percent of the initial metal oxide powder dissolved by nitric acid. BET measurements and TEM observations indicate that the 20%-La2O3 sample has an increased specific surface area, relatively thin and small crystallites in size. TPD/TPR profiles also show that the 20%-La2O3 sample has more surface active oxygen than the 0%-La2O3 sample. Among the four X%-La2O3 samples, the highest activity for methane oxidation was obtained over the 20%-La2O3 sample. Therefore, the present work proves that the method of partial dissolution and regrowth of crystallites are effective to modify surface property of lanthanum oxide.

关键词： solid state reaction surface oxygen crystallite regrowth TPR metal oxide

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Static Structure of Two-Dimensional Granular Chain

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Chinese Physics Letters 2010年第12期27卷 121-123页

作者：文平平李粮生郑宁史庆藩 Key Laboratory of cluster science of Ministry of Education and Department of Physics Beijing Institute of Technology Beijing 100081

Static packing structures of two-dimensional granular chains are investigated experimentally. It is shown that the packing density approximates the saturation with the exponential law as the length of chain increases. The packing structures are globally disordered, while the local square crystallization is found by using the radial distribution function. This characteristic phase of chain packing is similar to a Hquid crystal state, and has properties between a conventional liquid and solid crystal.

关键词： Statistical physics and nonlinear systems

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Direct oxidation of methyl radicals in OCM process deduced from correlation of product selectivities

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Journal of Natural Gas Chemistry 2010年第5期19卷 534-538页

作者： Zhiming Gao Yuanyuan Ma Key Laboratory of cluster science Ministry of Education of China Department of Chemistry School of Science Beijing Institute of Technology Beijing 100081 China

Selectivity of hydrogen in reaction of oxidative coupling of methane （OCM） was evaluated over the MxOy-BaCO3 （MzOy： La2O3, Sm2O3, MgO, CaO） catalysts. Correlation of product selectivities was thus discussed. From the correlation of product selectivities, it is revealed that the carbon oxides （CO and CO2） were most probably formed from the direct oxidation of methyl radicals under the conditions adopted in the present work. This is also in accordance with the OCM mechanism proposed in literature.

关键词： oxidative coupling methane hydrogen mechanism radical

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Facilitating Service Discovery with Semantic Overlay

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Journal of Computer science & Technology 2006年第4期21卷 582-591页

作者：金海武浩宁小敏 cluster and Grid Computing Laboratory Huazhong University of Science and Technology Wuhan ~3007~ P.R. China

Service Oriented Architecture （SOA） and Peer-to-Peer （P2P） computing share many common characteristics. It is believed that the combination of the two emerging techniques is a very promising method in promoting the web services （WS）. Because the service discovery plays a key role in the integration, here a P2P-based framework to manage the knowledge of service and locating services is proposed. In this paper, the details of the principle, constructing and maintaining of service semantic overlay architecture have been described, and the way how the semantic overlay facilitates discovery of service resources is illustrated. To enable the semantic web service superiority, Service Ontology, which is considered as the service semantic model, is employed to depict service. The service discovery includes two phases： searching on the service semantic overlay; and local discovery in peer＇s service repository. Various solutions have been proposed to realize those two phases. Furthermore, tests are carried out to evaluate service discovery on the architecture.

关键词： information search and retrieval intelligent web services semantic web knowledge management

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The Morphological Change of Silver Nanoparticles in Water

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Chinese Physics Letters 2012年第1期29卷 261-263页

作者： WANG Peng WANG Rong-Yao JIN Jing-Yang XU Le SHI Qing-Fan School of Physics and Key Laboratory of Cluster Science of Ministry of EducationBeijing Institute of TechnologyBeijing 100081

The solvent-induced morphological change of silver nanoparticles is studied with a combination of optical spectroscopy and atomic force microscopy(AFM).By using the local surface plasmon resonance(LSPR)spectroscopy arising from Ag nanoparticles,an in-situ investigation of the spectral changes is carried out before,during and after exposure of Ag island films to *** with the morphological observations by AFM,we sort out the morphological and dielectric contributions to the water-induced LSPR *** results demonstrate that a slight morphological change induced by water contact can result in an apparent blue shift of the LSPR spectral ***,it is found that this structural change leads to a higher sensitivity of the Ag island films in response to the change in the external dielectric *** solvent-induced morphological change,and consequently the modification of the LSPR of the metal nanoparticles,may have significant impact in the applications of solvent-involved plasmon sensors,such as chemical/biological sensing and single-molecule spectroscopy.

关键词： spectroscopy. nanoparticles Silver

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