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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China
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作者 SHI Xiaoliang CHEN Jiajun +2 位作者 DING Hao YANG Yuanqi ZHANG Yan 《Chinese Geographical Science》 SCIE CSCD 2024年第2期342-356,共15页
Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous r... Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790),the SSA-RF model has higher prediction accuracy for wet year(2018)(R^(2)=0.820).This study could provide an innovative approach for remote sensing estimation of winter wheat yield.yield. 展开更多
关键词 winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time henan Province China
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Assimilation of the FY-4A AGRI Clear-Sky Radiance Data in a Regional Numerical Model and Its Impact on the Forecast of the“21·7”Henan Extremely Persistent Heavy Rainfall 被引量:4
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作者 Lan XU Wei CHENG +5 位作者 Zhongren DENG Juanjuan LIU Bin WANG Bin LU Shudong WANG Li DONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第5期920-936,共17页
Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional ob... Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional observations for the“21·7”Henan extremely heavy rainfall is analyzed and compared with a baseline test that assimilates only conventional observations in this study.The results show that the 24-h cumulative precipitation forecast by the assimilation experiment with the addition of the AGRI exceeds 500 mm,compared to a maximum value of 532.6 mm measured by the national meteorological stations,and that the location of the maximum precipitation is consistent with the observations.The results for the short periods of intense precipitation processes are that the simulation of the location and intensity of the 3-h cumulative precipitation is also relatively accurate.The analysis increment shows that the main difference between the two sets of assimilation experiments is over the ocean due to the additional ocean observations provided by FY-4A,which compensates for the lack of ocean observations.The assimilation of satellite data adjusts the vertical and horizontal wind fields over the ocean by adjusting the atmospheric temperature and humidity,which ultimately results in a narrower and stronger WV transport path to the center of heavy precipitation in Zhengzhou in the lower troposphere.Conversely,the WV convergence and upward motion in the control experiment are more dispersed;therefore,the precipitation centers are also correspondingly more dispersed. 展开更多
关键词 FY-4A AGRI clear-sky radiance satellite data assimilation “21·7”henan extremely persistent heavy rainfall
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Preface to the Special Collection on the July 2021 Zhengzhou, Henan Extreme Rainfall Event 被引量:1
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作者 Ming XUE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第3期335-336,共2页
A period of extreme rainfall occurred from 17 to 22 July 2021 in Henan Province of China where the accumulated precipitation in the 6-day period exceeded 1000 mm, which is more than the mean annual precipitation in th... A period of extreme rainfall occurred from 17 to 22 July 2021 in Henan Province of China where the accumulated precipitation in the 6-day period exceeded 1000 mm, which is more than the mean annual precipitation in the region. The rainfall was particularly intense on 20 July 2021, especially over Zhengzhou City, the capital of Henan Province and home to more than 10 million people. Hourly rainfall of 201.9 mm was measured at a station in Zhengzhou, breaking the station hourly rainfall record for all of China's Mainland. Major urban flooding occurred in Zhengzhou, leading to submerged subway trains and city road tunnels. 展开更多
关键词 MAINLAND Zhengzhou henan
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Spatiotemporal Evolution and Influencing Factors of Urban-rural Construction Land in Rural Industrialized Areas in China:Case Studies in Changyuan City and Xinxiang County of Henan Province
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作者 SHI Yanwen LI Xiaojian +1 位作者 HU Xueyao LI Zeyi 《Chinese Geographical Science》 SCIE CSCD 2023年第5期850-864,共15页
Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural ind... Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural industrialized areas in central China(Xinxiang County and Changyuan City of Henan Province).We used the average nearest neighbor index,spatial statistical analysis,and a structural equation model to analyze the spatiotemporal evolution and influencing factors of urban-rural construction land based on multisource spatial data and survey data.The results showed that:1)from 1975 to 2019,the spatial distribution of urban-rural construction land in rural industrialized areas had evolved from homogeneous distribution to local agglomeration.In terms of comparative analysis of cases,the spatial distribution of urban-rural construction land in Changyuan City had shown a trend from diffusion to agglomeration,and Xinxiang County had overall shown a spatial change from homogenization to agglomeration and then to regional integration development.2)The hot spots with increased urban-rural construction land significantly expanded,and they had a high degree of spatial overlap with industrial development.Among them,Xinxiang County was concentrated in central and marginal areas,and Changyuan was mainly concentrated in central urban areas.3)From the evolution of spatial proximity of urban-rural construction land,rural industrialized areas generally decline,showing the characteristics of internal differentiation in the rate of change.4)Industrial development,social economy,the policy environment,and urban development played a positive role in promoting the expansion of urban-rural construction land in rural industrialized areas.To promote the optimal use of regional land and the integrated development of urban-rural areas,we should combine the advantages of regional endowment,formulate development strategies according to local conditions,and adjust the way that land is used in a timely manner. 展开更多
关键词 urban-rural construction land rural industrialized areas spatiotemporal evolution influencing factors rural industrialization henan Province China
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Preface to the Special Issue Celebrating the 100th Anniversary of the Founding of Mathematics at Henan University
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《Chinese Quarterly Journal of Mathematics》 2023年第3期I0001-I0001,共1页
The journey of mathematics at Henan University traces back to the inception of the Department of Mathematics and Physics at Zhongzhou University in 1923.Over the course of a century,scholars across generations have sh... The journey of mathematics at Henan University traces back to the inception of the Department of Mathematics and Physics at Zhongzhou University in 1923.Over the course of a century,scholars across generations have shared their aspirations with our nation,shaping the destiny of our country.Through unwavering dedication,they have continuously enhanced the quality of mathematical education and laid the groundwork for an enduring academic legacy. 展开更多
关键词 henan education continuously
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Campus Landscape and Campus Culture of Henan University of Science and Technology
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作者 TIAN Mengqi 《Journal of Landscape Research》 2023年第1期85-88,共4页
Due to the differences in disciplines and regional cultural spirits,the campus landscape of Chinese universities has varying cultural connotations.Campus landscape is not only a reflection of regional school history a... Due to the differences in disciplines and regional cultural spirits,the campus landscape of Chinese universities has varying cultural connotations.Campus landscape is not only a reflection of regional school history and culture,but also a potential factor affecting students'ideology and values.At present,some colleges and universities in China only concern and consider the visual impact effect of campus landscape construction,while others take landscape planning and construction as an accessory of the main building,which seriously affects the soul guiding role of campus culture in campus landscape.The internal and external landscape pattern of Henan University of Science and Technology with landscape road and water system as the framework,as well as core scenic spots with rich cultural connotations,such as“Peony Dinghu map”,“Yueqin Lake”,embody the university history and culture,the characteristics of western Henan architecture and the specific campus culture positioning,providing a stark example for landscape planning and design of other colleges and universities in the future. 展开更多
关键词 henan University of Science and Technology CAMPUS LANDSCAPE CULTURE
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Analysis of Rainstorm Process over Henan Province of China in July 2021
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作者 Zhiyuan Chen Wei Wang 《Journal of Geoscience and Environment Protection》 2023年第10期184-200,共17页
Based on the data from the China National Meteorological Station and the fifth-generation reanalysis data of the European Center for Medium-Range Weather Forecasts, we investigated and examined the precipitation, circ... Based on the data from the China National Meteorological Station and the fifth-generation reanalysis data of the European Center for Medium-Range Weather Forecasts, we investigated and examined the precipitation, circulation, and dynamic conditions of the rainstorm in Henan in July 2021. The results show that: 1) This precipitation is of very heavy rainfall level, beginning on the 19<sup>th</sup> and lasting until the 21<sup>st</sup>, with a 3-hour cumulative precipitation of more than 200 mm at Zhengzhou station at 19:00 on the 20<sup>th</sup>. The major focus of this precipitation is in Zhengzhou, Henan Province, and it also radiates to Jiaozuo, Xinxiang, Kaifeng, Xuchang, Pingdingshan, Luoyang, Luohe, and other places. 2) The Western Pacific Subtropical High (WPSH), typhoons “In-Fa” and “Cempaka”, as well as the less dynamic strengthening of the Eurasian trough ridge structure, all contributed to the short-term maintenance of the favorable large-scale circulation background and water vapor conditions for this rainstorm in Henan. 3) The vertical structure of low-level convergence and high-level dispersion near Zhengzhou, together with the topographic blocking and lifting impact, produced favorable dynamic lifting conditions for this rainstorm. 展开更多
关键词 henan Rainstorm Circulation Pattern Vertical Profile Dynamic Factors
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Analysis of Extreme Precipitation Weather Process in Henan during July 17-22, 2021
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作者 Zhaojin Wang 《Journal of Geoscience and Environment Protection》 2023年第4期72-85,共14页
To learn more about the unusually heavy rainfall in central China, this research uses the monthly climatic data, weather map information and US NCEP re-analysis data to analyze the atmospheric circulation, precipitati... To learn more about the unusually heavy rainfall in central China, this research uses the monthly climatic data, weather map information and US NCEP re-analysis data to analyze the atmospheric circulation, precipitation and weather situation of this extreme precipitation weather process in Henan during July 17-22, 2021. The results show that the precipitation process is affected by the joint action of the subtropical high, the continental high, the low vortex, the low-level jet, the typhoon “In-fa” and other multi-scale systems in the middle and low latitudes. This precipitation process was also affected by the topographic uplift and blocking of Taihang Mountain and Funiu Mountain. 展开更多
关键词 Extreme Precipitation Weather henan Province Subtropical High Typhoon “In-Fa” Topographic Action
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Trend, Mechanism and Path: Analysis of the Integrated Development of Henan Intangible Cultural Heritage and Tourist Industry with Digital Empowerment
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作者 Liu Yingji Hou Yi 《China & The World Cultural Exchange》 2023年第4期12-15,共4页
Up till now,Henan has established a relatively perfect Intangible Cultural Heritage listing system and protection system,which lays a foundation for the digitalization of Intangible Cultural Heritage.Meanwhile,Henan h... Up till now,Henan has established a relatively perfect Intangible Cultural Heritage listing system and protection system,which lays a foundation for the digitalization of Intangible Cultural Heritage.Meanwhile,Henan has vigorously carried out research on the activation of digital Intangible Cultural Heritage,resulting in improving the capabilities of digital application of Intangible Cultural Heritage. 展开更多
关键词 henan PERFECT INTANGIBLE
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Traveling to Henan,Understanding China
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《China & The World Cultural Exchange》 2023年第9期22-23,共2页
From July 30 to August 5,2023,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Henan Overseas Promotion Week",presenting to the global public"Traveling to Henan,Understanding China-H... From July 30 to August 5,2023,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Henan Overseas Promotion Week",presenting to the global public"Traveling to Henan,Understanding China-Henan Province Characteristic Tourism Cultural Resources Photo Exhibition"and"Traveling to Henan. 展开更多
关键词 henan EXHIBITION TOURISM
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猪繁殖与呼吸综合征河南毒株Henan-1的分离及其NSP2、ORF3、ORF5的序列分析 被引量:13
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作者 张彩勤 王旭荣 +2 位作者 杨增岐 赵炳武 宋长绪 《西北农业学报》 CSCD 北大核心 2008年第1期1-6,共6页
将2007年1月河南省某猪场送检的疑似高热病病料处理后接种于Marc-145细胞,出现细胞聚集、固缩、脱落等特异性细胞病变。根据GenBank中猪繁殖与呼吸综合征病毒(PRRSV)的基因序列设计并合成针对NSP2、ORF3和ORF5基因的引物,RT-PCR扩... 将2007年1月河南省某猪场送检的疑似高热病病料处理后接种于Marc-145细胞,出现细胞聚集、固缩、脱落等特异性细胞病变。根据GenBank中猪繁殖与呼吸综合征病毒(PRRSV)的基因序列设计并合成针对NSP2、ORF3和ORF5基因的引物,RT-PCR扩增目的基因并将其克隆入pMD18-T载体进行测序。并与国内外已发表的毒株的序列进行比较。结果表明:分离毒株Henan-1是美洲型PRRSV,而且NSP2基因发生30个AA的不连续缺失;Henan-1的NSP2、ORF3和ORF5基因与JXA1、JX0612、HZ-X、HB-1(sh)、CH-1a、HB-2(sh)、SP、ATCC VR-2332、Henan-HN1、Resp PRRS/Repro MLV、PA8、BJ-4等毒株等位基因的核苷酸同源性分别为83.0%~99.0%、88.3%~99.2%、88.6%~99.5%,推导的氨基酸同源性分别为66.7%~97.9%、84.7%~98.8%、87.1%~99.5%;而ORF3和ORF5基因与LV4.2.1等位基因核苷酸同源性分别为64.7%和64.2%,推导的氨基酸同源性分别为56.7%和61.0%。基因系统发育树分析表明:Henan-1与JXA1、JX0612株的亲缘关系很近,与HB-1(sh)亲缘关系较近,与HZ-X、CH-1a、HB-2(sh)、SP、RespPRRS/Repro MLV等毒株处于不同的分支。 展开更多
关键词 猪繁殖与呼吸综合征病毒 henan-1毒株 序列分析
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Evolution of the Mesozoic Granites in the Xiong'ershan-Waifangshan Region,Western Henan Province,China,and Its Tectonic Implications 被引量:58
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作者 NAN Yigui ZHANG Shihong +1 位作者 Franco PIRAJNO ZHANG Yuanhou 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第2期253-265,共13页
Based on the new data of isotopic ages and geochemical analyses, three types of Mesozoic granites have been identified for the Xiong'ershan-Waifangshan region in western Henan Province: high-Ba-Sr I-type granite emp... Based on the new data of isotopic ages and geochemical analyses, three types of Mesozoic granites have been identified for the Xiong'ershan-Waifangshan region in western Henan Province: high-Ba-Sr I-type granite emplaced in the early stage (-160 Ma), I-type granite in the middle stage (-130 Ma) and anorogenic A-type granite in the late stage (-115 Ma). Geochemical characteristics of the high-Ba-Sr I-type granite suggest that it may have been generated from the thickened lower crust by partial melting with primary residues of amphibole and garnet. Gradual increase of negative Eu anomaly and Sr content variations reflect progressive shallowing of the source regions of these granites from the early to late stage. New ^40Ar/^39Ar plateau ages of the early-stage Wuzhangshan granite (156.0±1.1 Ma, amphibole) and middle-stage Heyu granite (131.8±0.7 Ma, biotite) are indistinguishable from their SHRIMP U-Pb ages previous published, indicating a rapid uplift and erosion in this region. The representative anorogenic A- type granite, Taishanmiao pluton, was emplaced at -115 Ma. The evolution of the granites in this region reveals a tectonic regime change from post-collisional to anorogenic between -160 Ma and -115 Ma. The genesis of the early- and middle-stage I-type granites could be linked to delamination of subducted lithosphere of the Qinling orogenic belt, while the late-stage A-type granites represent the onset of extension and the end of orogenic process. In fact, along the Qiniing -Dabie-Sulu belt, the Mesozoic granitoids in western Henan, Dabieshan and Jiaodong regions are comparable on the basis of these temporal evolutionary stages and their initial ^87Sr/^86Sr ratios, which may suggest a similar geodynamic process related to the collision between the North China and Yangtze cratous. 展开更多
关键词 granite MESOZOIC high Ba-Sr ^40Ar/^39Ar dating POST-COLLISION ANOROGENIC western henan
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LA-ICP-MS Zircon U-Pb Geochronology of Quartz Porphyry from the Niutougou Gold Deposit in Songxian County,Henan Province 被引量:17
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作者 WANG Zhongliang GONG Qingjie +2 位作者 SUN Xiang WU Fafu WANG Weixing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期370-382,共13页
The Niutougou gold deposit, located in the center of the Xiong'ershan gold district, western Henan Province, is a large gold deposit with many quartz porphyries found in the area. Based on the field geological invest... The Niutougou gold deposit, located in the center of the Xiong'ershan gold district, western Henan Province, is a large gold deposit with many quartz porphyries found in the area. Based on the field geological investigation of quartz porphyry of Niutougou gold deposit and by using the cathodoluminescence (CL) images analysis and in situ LA-ICP-MS U-Pb isotope dating method of zircons, the inner structure, trace element compositions and U-Pb age of the zircons separated from quartz porphyry were analyzed and determined. Cathodoluminescence (CL) images of zircons show clear magmatic zonations. Trace element analyses of zircons reveal that all zircons show high concentrations of Th, U, and HREE, and the REE patterns of depletion in LREE, with a positive Ce anomaly. Zircon LA-ICP-MS U-Pb dating results show that the quartz porphyry in the Niutougou gold deposit was formed at 159.714-0.99 Ma (about 160 Ma), belonging to the product of magmatic activity in late Middle Jurassic. Combined with the geological characteristics of the Niutougou gold deposit, the formation age of the quartz porphyry and the analysis of the formation age of the granite body exposed in the Niutougou gold deposit, the study suggests that the metallogenic epoch of the Niutougou gold deposit may be Yanshanian in age. 展开更多
关键词 quartz porphyry zircon U-Pb chronology Niutougou Songxian County henan Province
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Cancer incidence and mortality in Henan province,2012 被引量:8
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作者 Shuzheng Liu Qiong Chen +5 位作者 Peiliang Quan Meng Zhang Shaokai Zhang Lanwei Guo Xibin Sun Chengzeng Wang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第3期275-285,共11页
Objective: Population-based cancer registration data in 2012 from all available cancer registries in Henan province were collected by Henan Office for Cancer Research and Control. The numbers of new cancer cases and ... Objective: Population-based cancer registration data in 2012 from all available cancer registries in Henan province were collected by Henan Office for Cancer Research and Control. The numbers of new cancer cases and cancer deaths in Henan province with compiled cancer incidence and mortality rates were estimated. Methods: In 2015, all registries' data in Henan province were qualified for the national cancer registry annual report in 2012. The pooled data were stratified by area (urban/rural), gender, age group (0, 1-4, 5-9, 10-14, ..., 85+) and cancer type. New cancer cases and deaths were estimated using age-specific rates and corresponding population of Henan province in 2012. The Chinese census data in 2000 and Segi's population were applied for age-standardized rates. All the rates were expressed per 100,000 person-years. Results: Qualified 19 cancer registries (4 urban and 15 rural registries) covered 16,082,688 populations of Henan province in 2012. The percentage of cases with morphologically verified (MV%) and death certificate- only cases (DCO%) were 69.84% and 2.30%, respectively, and the mortality to incidence rate ratio (M/ I) was 0.64. It was estimated that there were 248,510 new cancer cases and 158,630 cancer deaths in Henan province in 2012. The incidence rate was 266.17/100,000 (288.61/100,000 in males and 241.86/100,000 in females), the age-standardized incidence rates by Chinese standard population (ASIRC) and by world standard population (ASIRW) were 208.95/100,000 and 206.41/100,000 with the cumulative incidence rate (0-74 years old) of 24.30%. The crude incidence rate in urban areas was higher than that in rural areas. However, after adjusted by age, the cancer incidence rate in rural was higher than that in urban areas. The crude mortality of all cancers in Henan province was 169.90/100,000 (201.23/100,000 in males and 135.95/100,000 in females). The age-standardized mortality rates by Chinese standard population (ASMRC) and by world standard population (ASMRW) were 131.20/100,000 and 130.80/100,000, respectively. Among the patients aged 0-74 years, the cumulative mortality rate was 15.03%. The crude cancer mortality rate in urban areas was higher than that of rural areas. However, the age-standardized rate in rural areas was higher than that of urban areas. Cancers of lung, stomach, esophagus, liver, female breast, colorectum, cervix, brain, uterus and ovary were the most common cancers, accounting for about 82.80% of all cancer new cases. Lung cancer, stomach cancer, esophageal cancer, liver cancer, colorectal cancer, female breast cancer, brain cancer, leukemia, pancreatic cancer and cervix cancer were the leading causes of cancer deaths, accounting for about 88.50% of all cancer deaths. The burden between urban and rural, males and females were different. Conclusions: Registration data of Henan province was qualified to provide basic information on population-based cancer incidence, mortality for cancer prevention and control. The upper digestive tract cancer burden in Henan province, especially for males in rural areas, was higher. The incidence rate of female breast cancer was higher in urban areas. Targeted prevention, early detection and treatment programs should be carried out by health department to control the cancer burden. 展开更多
关键词 Cancer registry INCIDENCE MORTALITY EPIDEMIOLOGY henan province
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A New Sauropod Dinosaur from the Late Cretaceous Gaogou Formation of Nanyang,Henan Province 被引量:5
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作者 ZHANG Xingliao Lǔ Junchang +6 位作者 XU Li LI Jinhua YANG Li HU Weiyong JIA Songhai JI Qiang ZHANG Chengjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第2期212-221,共10页
A new sauropod dinosaur Baotianmansaurus henanensis gen. et sp. nov. from the Cretaceous Gaogou Formation of Neixiang, Henan Province is erected. It is characterized by somphospondylous presacral vertebrae; a highly-d... A new sauropod dinosaur Baotianmansaurus henanensis gen. et sp. nov. from the Cretaceous Gaogou Formation of Neixiang, Henan Province is erected. It is characterized by somphospondylous presacral vertebrae; a highly-developed lamina system on the dorsal vertebrae; transverse process supported by four laminae; and the dorsal portion of the anterior centroparapophyseal lamina is bifurcated, with a small branch extending to the ventral surface of the prezygapophysis. It represents a new titanosauriform sauropod. 展开更多
关键词 Titanosauriform Baotianmansaurus Gaogou Formation Late Cretaceous Nanyang henan Province
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Comparative studies on epithelial lesions at gastric cardia and pyloric antrum in subjects from a high incidence area for esophageal cancer in Henan,China 被引量:8
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作者 GAO ShanShan1, ZHOU Qi1, LI YongXin1, BAI YongMin1, ZHENG ZuoYu1, ZOU JianXiang1, LIU Gang1, FAN ZongMin1, QI YiJun1, ZHAO Xin1 and WANG LiDong1,2Keywords esophageal neoplasms stomach neoplasms gastric ca 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第4期60-61,共2页
Comparativestudiesonepitheliallesionsatgastriccardiaandpyloricantruminsubjectsfromahighincidenceareaforesoph... ComparativestudiesonepitheliallesionsatgastriccardiaandpyloricantruminsubjectsfromahighincidenceareaforesophagealcancerinHena... 展开更多
关键词 esophageal CARDIA INCIDENCE henan
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Regional agricultural landscape pattern changes along the Yellow River in Henan Province from 1987 to 2002 被引量:5
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作者 LIANG Guofu DING Shengyan LI Zhiheng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期415-422,共8页
Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the cha... Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the change of agricultural landscape along the riparian zones is at the top of the agenda for many policy makers and landscape planners. As a basis for conservation management, sufficient information about landscape structure should be provided. In the present study, we reconstructed the former landscape structure and elucidated the changes in landscape patterns during a period of about 15 years. Two sets of maps were used: a landsat-5 TM image (1987) and landsat-7 ETM image (2002). The frequency index, landscape diversity index and landscape fragmentation index were calculated for analyses. The results showed that: (1) the areas of the irrigated land, river, forest and beach landscape classes presented a decreasing trend while the areas of landscape classes of pool, paddy fields, dry land and construction land increased. (2) Disturbed by human activity, landscape diversity index increased but landscape fragmentation index decreased. In short, Human activities have had important influences on agricultural landscape of the riparian zones along the Yellow River in Henan Province. 展开更多
关键词 agricultural landscape landscape pattern change the Yellow River henan Province
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Dynamics of forest biomass carbon stocks from 1949 to 2008 in Henan Province,east-central China 被引量:5
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作者 Yanfang Wang Ling Liu Zhouping Shangguan 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期434-443,共10页
We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests w... We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub forests.We estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor method.We used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub forests.Over the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10;g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 Tg.By stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub forests.Carbon storageincreased at an average annual rate of 0.8 Tg carbon over the study period.Carbon was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory periods.Broad-leaved forest was the main contributor to forest carbon sequestration.From 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 Tg.Our results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program. 展开更多
关键词 Forest biomass carbon stock Forest resource inventory henan Province
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Description and Phylogenetic Position of Dinosaur Eggshells from the Luanchuan Area of Western Henan Province,China 被引量:3
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作者 Kohei TANAKA LU Junchang +5 位作者 Yoshitsugu KOBAYASHI Darla K. ZELENITSKY XU Li JIA Songhai QIN Shuang TANG Min' an 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第1期66-74,共9页
Here, we examine 145 dinosaur eggshells from a new fossil locality in the Qiupa Formation (Upper Cretaceous) of the Luanchuan area in western Henan Province, China. The eggshells display elongatoolithid macro- and m... Here, we examine 145 dinosaur eggshells from a new fossil locality in the Qiupa Formation (Upper Cretaceous) of the Luanchuan area in western Henan Province, China. The eggshells display elongatoolithid macro- and microstructures, including ridges and nodes on the outer surface, two ultrastructurai layers, and an undulatory boundary between the mammillary and continuous layers. A phylogenic analysis shows that the Luanchuan eggshells belong to the ooclade Elongatoolithidae. Within Elongatoolithidae, the thickness ratio of the mammillary layer to the entire eggshell, and the porosity of the Luanchuan eggshells are comparable to the oogenera Macroolithus and Elongatoolithus. There is no direct evidence for the taxonomic identity of the Luanchuan eggshells; however, they were likely laid by oviraptorids based on their phylogenetic position and their similarities with known oviraptorid eggs. 展开更多
关键词 dinosaur eggshells Qiupa Formation Late Cretaceous Luanchuan henan Province China
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A New Lizard(Lepidosauria:Squamata) from the Upper Cretaceous of Henan,China 被引量:2
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作者 XU Li WU Xiaochun +4 位作者 Lü Junchang JIA Songhai ZHANG Jiming PU Hanyong ZHANG Xingliao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第4期1041-1050,共10页
Funiusaurus luanchuanensis gen. et sp. nov. was described on the basis of an incomplete skull from the Upper Cretaceous Qiupa Formation of the Tantou Basin in Luanehuan County, Henan Province. It is the second represe... Funiusaurus luanchuanensis gen. et sp. nov. was described on the basis of an incomplete skull from the Upper Cretaceous Qiupa Formation of the Tantou Basin in Luanehuan County, Henan Province. It is the second representative of lizards known from Luanchuan and adds a new member to the Luanchuan Fauna. F. luanchuanensis is a small-sized lizard and systematically assigned to the Polyglyphanodontidae of the Teiioidea because of the presence of a caniniform tooth and an elongate posterior process of the postorbital. It is distinctive in that the heterodont dentition bears 19 teeth in both the upper and lower jaws, the 3^rd maxillary tooth is large and caniniform, the post-caniniform teeth in maxilla and those posterior to the 3^rd dentary tooth are chisel-like in lateral view, the prefrontal possesses a fossa on its lateral surface, the postorbital with an extremely elongate posterior process and the well-developed retroarticular process has a deep fossa on its dorsal surface. In phylogeny, our analysis suggests a close relationship of Funiusaurus to the large-sized Tianyusaurus from the same basin within the Tuberocephalosaurinae. The discovery of Funiusaurus is significant in confirming the status of the Tuberocephalosaurinae, which includes a group of the Asian members of the Polyglyphanodontidae only. 展开更多
关键词 SQUAMATA Funiusaurus Qiupa Formation Late Cretaceous henan
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