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Establishment and Application of Multiple RT-PCR for Detection of Three Yellow Dwarf Viruses

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Establishment and Application of Multiple RT-PCR for Detecti...

Distribution of Maize Yellow Mosaic Virus on Wheat and Maize in Henan Province and Variation of Their CP Sequences

中国植物病理学会2024年学术年会

作者： WANG He JIANG Xinglin HAN Xiaoyu xu yongwei PENG Hong WANG Yifan YUAN Hongxia LI Honglian Yang xue SHI Yan College of Plant Protection Henan Agricultural University Henan Plant Protection and Plant Quarantine Station Collaborative Innovation Centre of Henan Grain crops State Key Laboratory of Wheat and Maize Crop Science Crop science postdoctoral programme of Henan Agricultural University

Wheat yellow dwarf disease causes typical disease symptoms such as yellowing,and stunting and reduced seed size and yield,leading to severe economic *** wheat *** and BYDV-GAV are two main viruses causing yellow dwarf in *** was recently reported to cause yellow dwarf in *** this study diseased leaf samples showing yellowing and stunting on wheat leaves were collected in different regions in Henan province in *** optimal reaction condition for multiple RT-PCR detection of BYDV-PAV,BYDV-GAV and MaYMV was screened and established with following condition:final primer concentration at 0.1 μmol/L,annealing temperature at 55℃,annealing and extension time of 60 s and 90 s,*** further used the established multiple RTPCR system to detect 19 field samples which showed that 11 out of 19 samples were positive for BYDVPAV and MaYMV indicating that the mix infection of BYDV-PAV and MaYMV was commonly occurred in the *** study laid the foundation for the field surveillance and control of wheat yellow dwarf disease in Henan Province.

关键词： MaYMV BYDV-PAV BYDV-GAV coat protein multiple RT-PCR wheat

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Distribution of Maize Yellow Mosaic Virus on Wheat and Maize...

Conversion of CH4, steam and O_2 to syngas and hydrocarbons via dielectric barrier discharge

中国植物病理学会2024年学术年会

作者： XIE Lina ZHANG Yuyang YU Lianwei xu yongwei YANG xue WANG Yafei CHEN Linlin LI Honglian CUI Yingjun SHI Yan College of Plant Protection Henan Agricultural University Henan Plant Protection and Plant Quarantine Station Collaborative Innovation Centre of Henan Grain Crops State Key Laboratory of Wheat and Maize Crop Science Henan Plant Protection New Technology Promotion Association

Maize yellow mosaicvirus(MaYMV) as a newly identified polerovirus causes leaf reddening on maize and yellow dwarf on wheat,leading to severe economic *** this study,maize and wheat leaf samples showing viral symptoms were collected in 11 different regions in Henan province in *** results of their full length coat protein nucleotide and amino acid sequence showed that MaYMV was commonly distributed in Henan province with the highest detection rate of 100% in wheat from Zhumadian and Xinxiang66.7% in maize from *** amino acid identity was high between different isolates with a variation rate between 0%-2.0%.Further phylogenetic analysis showed that the maize and wheat isolates of MaYMV were clustered into a major *** study lays a foundation for the surveillance and control of MaYMV.

关键词： MaYMV coat protein phylogenetic analysis maize wheat

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Journal of Natural Gas Chemistry 2009年第1期18卷 94-97页

作者： Baowei Wang xu Zhang yongwei Liu Genhui xu Key Laboratory for Green Chemical Technology of the Ministry qf Education School qf Chemical Engineering and Technology. Tianjin University Tianjin 300072 China

The conversion of CH4 with oxygen and steam in a dielectric barrier discharge （DBD） was studied in the paper to discuss the effects of different factors, such as the content of feed-in gas, the applied voltage and frequency. The results showed that a lower ratio of CH4 to O2 always resulted in a higher conversion of CH4. When it was 2, the conversion reached 32.43% without steam introduced into the system. The main effect of steam was increasing the selectivity to CO. The reaction was accelerated and the selectivities to CO and hydrocarbons were enhanced by increasing the applied voltage. It was also observed that a higher frequency led to a lower current and then restrained the reaction.

关键词： methane steam oxygen dielectric barrier discharges plasma

2013—2022年河南省花生病虫害发生特点、原因与防控对策

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中国植保导刊 2024年第5期44卷 30-35页

作者：张国彦徐永伟李好海周琳崔荧钧张如意河南省植物保护检疫站河南郑州450002 河南农业大学河南郑州450002 河南省植物保护新技术推广协会河南郑州450002 河南省夏邑县农业农村局河南夏邑476000

花生是河南省重要的经济作物,病虫害是影响花生生产的关键因素。本文分析了2013—2022年河南省花生病虫害发生特点,并从耕作制度、气候条件、品种抗性等几个方面对病虫发生原因进行了分析。近10年花生病虫害年均发生面积309.93万hm2次,... 详细信息

花生是河南省重要的经济作物,病虫害是影响花生生产的关键因素。本文分析了2013—2022年河南省花生病虫害发生特点,并从耕作制度、气候条件、品种抗性等几个方面对病虫发生原因进行了分析。近10年花生病虫害年均发生面积309.93万hm2次,是年均种植面积的2.72倍,病虫发生种类多、面积大、为害重;花生叶斑病、茎腐病、白绢病、棉铃虫、甜菜夜蛾、地下害虫等6种(类)病虫发生面积占比达到76.54%,成为河南省花生上的主要病虫;白绢病、甜菜夜蛾为害加重;花生蚜、叶螨发生呈下降趋势;整体上虫害发生面积大于病害发生面积。针对病虫发生情况,提出了农业防治、理化诱控、生物防治和科学用药等综合性防治措施,并对下一步花生病虫害防治工作提出了建议对策,为花生病虫害科学防治提供参考。

关键词：花生病虫害发生面积防控措施

大豆玉米带状复合种植田杂草防除技术集成试验

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杂草学报 2024年第1期42卷 56-61页

作者：毛奇闵红张国彦徐永伟马跃河南省植物保护检疫站河南郑州450002

为了集成适合大豆玉米带状复合种植田杂草防除的有效技术模式,于2023年开展土壤喷雾封闭、土壤喷雾封闭+茎叶喷雾补杀(“一封一补”)防除杂草的大区试验。结果表明,播后苗前使用80%砜吡草唑·嗪草酮WG 450 g/hm 2或45%精异丙甲草胺CS 15... 详细信息

为了集成适合大豆玉米带状复合种植田杂草防除的有效技术模式,于2023年开展土壤喷雾封闭、土壤喷雾封闭+茎叶喷雾补杀(“一封一补”)防除杂草的大区试验。结果表明,播后苗前使用80%砜吡草唑·嗪草酮WG 450 g/hm 2或45%精异丙甲草胺CS 1500 mL/hm 2+33%精异草·丙炔氟CS 1500 mL/hm 2进行土壤喷雾,对禾草的株防效在94%以上;45%精异丙甲草胺CS 1500 mL/hm 2+33%精异草·丙炔氟CS 1500 mL/hm 2土壤喷雾、80%砜吡草唑·嗪草酮WG 450 g/hm 2土壤喷雾封闭+480 g/L灭草松AS 3000 mL/hm 2茎叶喷雾对禾草及阔叶杂草的综合防效达94%以上。集成了适合禾草化除的“土壤封闭”模式、禾阔双除的“土壤封闭”模式以及“一封一补”模式,安全性高,在登记的基础上,可用于河南省大豆玉米带状复合种植田杂草防治。土壤喷雾后,必须通过浇水或降雨来增加土壤墒情,才能较好地发挥药效。

关键词：大豆玉米带状复合种植土壤喷雾一封一补杂草防除

Debris Flow Susceptibility Evaluation in Meizoseismal Region:A Case Study in Jiuzhaigou,China

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Journal of Earth Science 2024年第1期35卷 263-279页

作者： yongwei Li Linrong xu Yonghui Shang Shuyang Chen School of Civil Engineering Central South UniversityChangsha 410075China National Engineering Research Center of High-Speed Railway Construction Technology Central South UniversityChangsha 410075China School of Civil Engineering Central South University of Forestry and TechnologyChangsha 410004China

Jiuzhaigou is situated on a mountain-canyon region and is famous for frequent tectonic *** abundance of loose co-seismic landslides and collapses were produced on gullies after the Jiuzhaigou Earthquake on August 8,2017,which was served as material source for debris flow in later *** flow appears frequently which are seriously endangering the safety of people's lives and *** the earliest debris flow appeared in areas where no case ever reported *** debris flow susceptibility evaluation(DFSE)is used for predicting the areas prone to debris flow,which is urgently required to avoid hazards and help to guide the strategy of preventive ***,this work employs debris flow in Jiuzhaigou to reveal the characteristics of disaster-pregnant environment and to explore the application of machine learning in *** new viewpoints are suggested:(i)Material density factor of debris flow is first adopted in this work,and it is proved to be a critical factor for triggering debris flows by sensitivity analysis method.(ii)Deep neural network and convolutional neural network(CNN)achieve relatively good area under the curve(AUC)values and are 0.021-0.024 higher than traditional machine learning methods.(iii)Watershed units combined with CNNbased model can achieve more accurate,reliable and practical susceptibility *** work provides an idea for prevention of debris flow in mountainous lands.

关键词： machine learning earthquakes debris flow susceptibility convolutional neural network deep neural network watershed unit

Method for C/N ratio estimation using Mask R-CNN and a depth camera for organic fraction of municipal solid wastes

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 222-229页

作者： Jingjing Huang Hongduo Zhang xu Xiao Jingqi Huang Jingxin Xie Liang Zhang Heming Hu Sihui Dai Ming Li yongwei xu College of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China Graduate School of Agricultural and Life Sciences the University of TokyoTokyo 113-0033Japan Hunan Agricultural Equipment Research Institute Changsha 410125China College of Horticulture Hunan Agricultural UniversityChangsha 410128China Center for Spatial Information Science University of TokyoKashiwa 277-8568Japan

Fast assessment of the initial carbon to nitrogen ratio(C/N)of organic fraction of municipal solid waste(OFMSW)is an important prerequisite for automatic composting control to improve efficiency and stability of the bioconversion *** this study,a novel approach was proposed to estimate the C/N of OFMSW,where an instance segmentation model was applied to predict the masks for the waste ***,by combining the instance segmentation model with the depth-camera-based volume calculation algorithm,the volumes occupied by each type of waste were obtained,therefore the C/N could be estimated based on the properties of each type of ***,an instance segmentation dataset including three common classes of OFMSW was built to train mask region-based convolutional neural networks(Mask R-CNN)***,a volume measurement algorithm was proposed,where the measurement result of the object was derived by accumulating the volumes of small rectangular cuboids whose bottom area was calculated with the projection *** the calculated volume was corrected with linear regression *** results showed that the trained instance segmentation model performed well with average precision scores AP_(50)=82.9,AP_(75)=72.5,and mask intersection over unit(Mask IoU)=45.1.A high correlation was found between the estimated C/N and the ground truth with a coefficient of determination R2=0.97 and root mean square error RMSE=*** relative average error was 0.42%and the maximum error was only 1.71%,which indicated this approach has potential for practical applications.

关键词： carbon to nitrogen ratio estimation volume measurement organic fraction of municipal solid waste depth camera instance segmentation

Optimizing write operation on replica in data grid

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Science China(Information Sciences) 2011年第1期54卷 1-11页

作者： xu PengZhi,WU yongwei,HUANG XiaoMeng, YANG GuangWen & ZHENG WeiMin Department of Computer Science and Technology,Tsinghua University,Beijing 100084,China Department of Computer Science and Technology Tsinghua University Beijing China

Replication technique can improve access performance and data availability of data grid systems. So far,most related work on data replication in data grid systems focuses on read-only *** write operations have been widely used in practice,its optimization problem has not been suciently *** this paper,we show that write requests from users can be processed by a nearest site,regardless of the location of latest written *** policy of write nearby instead of write to the latest replica can improve the performance of write operations,while inconsistency is caused between multiple ***,we propose two metadata management algorithms to make sure that users can retrieve up-to-date datasets at any *** extend OptorSim to support the implementation and evaluation of our *** results of simulation show that our scheme achieves performance gains up to 3.3 compared with WriteMaster scheme.

关键词： replication data grid simulation access latency

Recognition and localization of strawberries from 3D binocular cameras for a strawberry picking robot using coupled YOLO/Mask R-CNN

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International Journal of Agricultural and Biological Engineering 2022年第6期15卷 175-179页

作者： Heming Hu Yutaka Kaizu Hongduo Zhang yongwei xu Kenji Imou Ming Li Jingjing Huang Sihui Dai Graduate School of Agricultural and Life Sciences the University of TokyoTokyo 113-0033Japan Hunan Agricultural Equipment Research Institute ChangshaHunan 410125China College of Horticulture Hunan Agricultural UniversityChangshaHunan 410128China

To solve the problem of high labour costs in the strawberry picking process,the approach of a strawberry picking robot to identify and find strawberries is suggested in this ***,1000 images including mature,immature,single,multiple,and occluded strawberries were collected,and a two-stage detection Mask R-CNN instance segmentation network and a one-stage detection YOLOv3 target detection network were used to train a strawberry identification model which classified strawberries into two categories:mature and *** accuracy ratings for YOLOv3 and Mask R-CNN were 93.4%and 94.5%,***,the ZED stereo camera,triangulation,and a neural network were used to locate the strawberry in three ***3 identification accuracy was 3.1 mm,compared to Mask R-CNN of 3.9 *** strawberry detection and positioning method proposed in this study may effectively be used to supply the picking robot with a precise location of the ripe strawberry.

关键词： strawberry detection 3D point cloud mean-shift clustering method