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Ensemble learning prediction of soybean yields in China based on meteorological data

Journal of Integrative Agriculture 2023年第6期22卷 1909-1927页

作者： LI Qian-chuan XU Shi-wei ZHUANG Jia-yu LIU Jia-jia ZHOU Yi ZHANG Ze-xi Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Beijing Engineering research center for Agricultural Monitoring and early warning Beijing 100081P.R.China Aerospace Information research Institute Chinese Academy of SciencesBeijing 100094P.R.China The Department of Mathematics Columbia UniversityNY 10027USA Key Laboratory of Agricultural Monitoring and early warning Technology Ministry of Agriculture and Rural AffairsBeijing 100081P.R.China

The accurate prediction of soybean yield is of great significance for agricultural production, monitoring and early *** previous studies have used machine learning algorithms to predict soybean yield based on meteorological data,it is not clear how different models can be used to effectively separate soybean meteorological yield from soybean yield in various regions. In addition, comprehensively integrating the advantages of various machine learning algorithms to improve the prediction accuracy through ensemble learning algorithms has not been studied in depth. This study used and analyzed various daily meteorological data and soybean yield data from 173 county-level administrative regions and meteorological stations in two principal soybean planting areas in China(Northeast China and the Huang–Huai region), covering 34 *** effective machine learning algorithms(K-nearest neighbor, random forest, and support vector regression) were adopted as the base-models to establish a high-precision and highly-reliable soybean meteorological yield prediction model based on the stacking ensemble learning framework. The model's generalizability was further improved through 5-fold crossvalidation, and the model was optimized by principal component analysis and hyperparametric optimization. The accuracy of the model was evaluated by using the five-year sliding prediction and four regression indicators of the 173 counties, which showed that the stacking model has higher accuracy and stronger robustness. The 5-year sliding estimations of soybean yield based on the stacking model in 173 counties showed that the prediction effect can reflect the spatiotemporal distribution of soybean yield in detail, and the mean absolute percentage error(MAPE) was less than 5%. The stacking prediction model of soybean meteorological yield provides a new approach for accurately predicting soybean yield.

关键词： meteorological factors ensemble learning crop yield prediction machine learning county-level

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Spatial-Temporal Changes in Grain Production, Consumption and Driving Mechanism in China

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Journal of Integrative Agriculture 2013年第2期12卷 374-385页

作者： XU Shi-wei WU Jian-zhai SONG Wei LI Zhi-qiang LI Zhe-min KONG Fan-tao Key Laboratory of Digital Agricultural early-warning Technology Ministry of Agriculture/Agriculture Information Institute Chinese Academy of Agriculture Sciences Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences

The spatial-temporal patterns of grain production and consumption have an important influence on the effective national grain supply on condition of tight balance in the total grain amount in China. In this paper, we analyze the spatial-temporal pattems of grain production, consumption and the driving mechanism for their evolution processes in China. The results indicate that both gravity centers of grain production and consumption in China moved toward the northern and eastern regions, almost in the same direction. The coordination of grain production and consumption increased slightly from 1995 to 2007 but decreased from 2000 to 2007. There is a spatial difference between the major districts of output increase and the strong growth potential in grain consumption, which indicates an increasing difficulty in improving the regional coordination of grain production and consumption. The movement of the gravity center of grain production is significantly correlated with regional differences in grain production policy, different economic development models, and spatial disparity of land and water resource use. For grain consumption, the main driving factors include rapid urbanization, the upgrade of food consumption structure, and distribution of food industries.

关键词： grain production grain consumption gravity center driving mechanism

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Low Pathogenic Avian influenza A(H5N7) Virus Isolated from a Domestic Duck in Dongting Lake Wetland of China,2016

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Virologica Sinica 2019年第1期34卷 97-101页

作者： Liping Ma Haizhou Liu Runkun Wang Tao Jin Di Liu George Fu Gao Quanjiao Chen CAS Key Laboratory of Special Pathogens and Biosafety CAS Center for Influenza Research and Early WarningWuhan Institute of VirologyChinese Academy of Sciences University of Chinese Academy of Sciences China National Genebank-Shenzhen BGI-Shenzhen Savaid Medical School University of Chinese Academy of Sciences CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences

Dear Editor,The avian influenza virus (AIV) H5N7 was first isolated from wild birds in North America in 2001 (Spackman et al.2007), and information on only 25 strains of this virus has been deposited in the Global Initiative on Sharing All influenza Data (GISAID-http://***/epi3/frontend#493de3) database until October 30, 2018. Twenty viruses were identified in the United States from 2001 to2017.

关键词： HPAIV Virus Isolated from a Domestic Duck in Dongting Lake Wetland of China,2016 Low Pathogenic Avian influenza A

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Characteristics of the Two Active Stages of Lightning Activity in Two Hailstorms

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Journal of Meteorological research 2016年第2期30卷 265-281页

作者：徐爽郑栋王咏青胡鹏宇 School of Atmospheric Science Nanjing University of Information Science & Technology Shenyang Meteorological Administration State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Liaoning Meteorological Disaster Monitoring and early warning center

Two hailstorms that occurred in Beijing and Tianjin,respectively,are investigated,based mainly on the total lightning data observed by the System d＇Alerte Fondre par Interferometric Radioelecctrique（SAFIR3000）,the cloud-to-ground（CG） lightning data of a CG lightning location system,and the echo data of a Doppler *** hailstorms exhibited two lightning frequency peaks：the first was before the hailfall and the second was after the hailfall,with the second peak greater than the *** dominant polarity of the CG lightning was positive in the stage around the first frequency peak,but changed to negative in the stage around the second frequency *** evolution of radar echoes and the height distribution of lightning radiation sources are explored,revealing that both hailstorms had stronger convection and the main positive charge occurred at mid levels during the stage around the first frequency ***,whilst the Beijing hailstorm experienced the enhancement of convection,with the main positive charge at upper levels around the second frequency peak,the Tianjin hailstorm generated its second frequency peak during the period when the convection kept weakening and the main positive charge dropped to mid-lower *** evaluation of the radar parameters,we investigate the mechanisms responsible for the second stage of active lightning ***,the lightning activity exhibited a close relationship with radar echo parameters and *** jump signals were found before the hailfall and were associated with the change ratio of the 40-dBZ echo volume above the-15℃ level,which demonstrates the application value of lightning data in severe weather warning.

关键词： hailstorm total lightning electric structure

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Morbidity Analysis of the Notifiable Infectious Diseases in China,2018

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China CDC weekly 2019年第4期1卷 47-53页

作者： Shuaibing Dong Xiang Ren Cuihong Zhang Mengjie Geng Yuliang Zhu Lusha Shi Lijie Zhang Zhongjie Li Liping Wang Division of Infectious Disease Key Laboratory of Surveillance and Early Warning on Infectious DiseaseChina CDCBeijingChina Fuyang CDC AnhuiChina Heilongjiang CDC HeilongjiangChina Complex Systems research center Shanxi UniversityShanxiChina

Introduction Notifiable infectious disease surveillance is important for understanding the trends in morbidity for certain diseases,especially detection of acute infectious disease outbreaks and changing epidemiology.A web-based reporting system was deployed in January 2004,which has improved data collection and speed *** report provides an updated analysis for reports published in 2013 and *** Data from the National Notifiable Disease Reporting System(NNDRS)was *** NNRDS shows data from 39 notifiable diseases split into three categories(A,B,and C)based on severity and importance.A descriptive analysis was conducted to analyze the morbidity of notifiable diseases in *** In 2018,the morbidity of national notifiable diseases was 559.41 per 100,000 population,an increase of 12.88% compared with the average of 2015–*** proportion of laboratory confirmed cases was 36.22%,which decreased 4.03% compared with the average of that in the recent three *** transmitted by direct contact/fecal–oral transmission accounted for the largest proportion,49.37% of the total reported cases,followed by the respiratory transmitted diseases,blood-borne/sexually transmitted diseases,and the zoonotic and vectorborne diseases with a proportion of 25.18%,24.60%,and 0.85%,*** descriptive analysis showed that the viral-infected cases accounted for 73.78% of the totals,followed by the bacterialinfected and parasitic *** The national morbidity of notifiable infectious diseases showed increases in 2018,mostly due to higher morbidity of category C diseases,such as HFMD,infectious diarrhea,and influenza,and these diseases need to be further prioritized in disease control and prevention *** confirmed cases remain low and need to be improved to improve data quality.

关键词： Diseases epidemiology prevention

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research and application of real-time monitoring and early warning thresholds for multi-temporal agricultural products information

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Journal of Integrative Agriculture 2020年第10期19卷 2582-2596页

作者： XU Shi-wei WANG Yu WANG Sheng-wei LI Jian-zheng Key Laboratory of Agricultural Information Service Technology of the Ministry of Agriculture and Rural Affairs Bejing 100081P.R.China research center of Agricultural Monitoring and early warning Engineering Technologies Beijing 100081P.R.China Key Open Laboratory of Itelligent Agricultural early warning Technologies and Systems Chinese Academy of Agricultural SciencesBejjing 100081P.R.China Agriculture Information Institute Chinese Academy of Agricultural SciencesBeiing 100081P.R.China

Monitoring and early warning is an important means to effectively prevent risks in agricultural production,consumption and *** particular,with the change of modes of national administration against the background of big data,improving the capacity to monitor agricultural products is of great significance for macroeconomic *** product information early warning thresholds are the core of agricultural product monitoring and early *** to appropriately determine the early warning thresholds of multi-temporal agricultural product information is a key question to realize real-time and dynamic monitoring and early *** on the theory of abnormal fluctuation of agricultural product information and the research of substantive impact on the society,this paper comprehensively discussed the methods to determine the thresholds of agricultural product information fluctuation in different time *** on the data of the National Bureau of Statistics of China(NBSC)and survey data,this paper used a variety of statistical methods to determine the early warning thresholds of the production,consumption and prices of agricultural *** with Delphi expert judgment correction method,it finally determined the early warning thresholds of agricultural product information in multiple time,and carried out early warning analysis on the fluctuation of agricultural product monitoring information in *** results show that:(1)the daily,weekly and monthly monitoring and early warning thresholds of agricultural products play an important early warning role in monitoring abnormal fluctuations with agricultural products;(2)the multitemporal monitoring and early warning thresholds of agricultural product information identified by the research institute can provide effective early warning on current abnormal fluctuation of agricultural product information,provide a benchmarking standard for China's agricultural production,consumption a

关键词： agricultural product information monitoring and early warning threshold multi-temporal real-time dynamics

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Cross-species recognition and molecular basis of SARS-CoV-2 and SARS-CoV binding to ACE2s of marine animals

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National Science Review 2022年第9期9卷 166-177页

作者： Shihua Li Ruirui Yang Di Zhang Pu Han Zepeng Xu Qian Chen Runchu Zhao Xin Zhao Xiao Qu Anqi Zheng Liang Wang Linjie Li Yu Hu Rong Zhang Chao Su Sheng Niu Yanfang Zhang Jianxun Qi Kefang Liu Qihui Wang George F.Gao CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences College of Veterinary Medicine Shanxi Agricultural University Faculty of Health Sciences University of Macau Institute of Physical Science and Information Anhui University center for influenza research and early-warning(CASCIRE) Chinese Academy of Sciences Savaid Medical School University of Chinese Academy of Sciences School of Life Sciences University of Science and Technology of China State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangxi University

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) has an extremely broad host range that includes hippopotami,which are phylogenetically closely related to *** cellular ACE2 receptor is one of the key determinants of the host ***,we found that from several marine mammals and hippopotami could efficiently bind to the receptor-binding domain(RBD) of both SARS-C oV and SARS-C oV-2 and facilitate the trans duction of SARS-C oV and SARS-C oV-2 pseudo viruses into ACE2-expressing *** further resolved the cryo-electron microscopy complex structures of the minke whale ACE2 and sea lion ACE2,respectively,bound to the RBDs,revealing that they have similar binding modes to human ACE2 when it comes to the SARS-C oV-2 RBD and SARS-C oV *** results indicate that marine mammals could potentially be new victims or virus carriers of SARS-C oV-2,which deserves further careful investigation and *** will provide an early warning for the prospective monitoring of marine mammals.

关键词： marine animals SARS-CoV-2 cross-species recognition cryo-EM structure

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Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha J.Holdsworth Alistair J.Gunn Laura Bennet Hamid Abbasi Mātai Medical research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand center for Brain research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

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Genetic tracing of HCoV-19 for the re-emerging outbreak of COVID-19 in Beijing, China

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Protein & Cell 2021年第1期12卷 4-6页

作者： Jing Yang Peihua Niu Lijuan Chen Liang Wang Li Zhao Baoying Huang Juncai Ma Songnian Hu Linhuan Wu Guizhen Wu Chun Huang Yuhai Bi Wenjie Tan CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyCenter for Influenza Research and Early-warning(CASCIRE)CAS-TWAS Center of Excellence for Emerging Infectious Diseases(CEEID)Chinese Academy of SciencesBeijing 100101China National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention(China CDC)Beijing 102206China Beijing center for Diseases Prevention and Control Beijing 100013China center for Biosafety Mega-Science Chinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 101408China

The ongoing pandemic of coronavirus disease 2019(COVID-19)caused by a novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2,also named as 2019-nCoV or HCoV-19)poses an unprecedented threat to public health(Zhu et al.,2020;Wang et al.,2020;Jiang et al.,2020).The novel HCoV-19 virus has rapidly spread into multiple countries across the world since it was first reported in December *** World Health Organization(WHO)declared COVID-19 as a pandemic on 11th March *** of 4th July,over 10 million confirmed COVID-19 cases have been reported in over 200 countries/regions with more than 0.5 million deaths,including 85,287 documented cases and 4,648 deaths in China(WHO,2020a).

关键词： al. acute respiratory

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Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration research 2025年第9期20卷 2598-2610页

作者： Yi Wang Yuning Li Yakun Gu Wei Ma Yuying Guan Mengyuan Guo Qianqian Shao Xunming Ji Jia Liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

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