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A New Post-hoc Flat Field Measurement Method for the Solar X-Ray and Extreme Ultraviolet Imager Onboard the FengYun-3E Satellite

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Research in Astronomy and Astrophysics 2022年第10期22卷 1-10页

作者： Qiao Song Xianyong Bai Bo Chen Xiuqing Hu Yajie Chen Zhenyong Hou Xiaofan Zhang Lingping He Kefei Song Peng Zhang Jing-Song Wang Xiaoxin Zhang Weiguo Zong Jinping Dun Hui Tian Yuanyong Deng Key Laboratory of Space Weather National Satellite Meteorological Center(National Center for Space Weather)China Meteorological AdministrationBeijing 100081China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China Innovation center for Fengyun Meteorological Satellite China Meteorological AdministrationBeijing 100081China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological Center(National Center for Space Weather)China Meteorological AdministrationBeijing 100081China School of Earth and Space Sciences Peking UniversityBeijing 100871China

Extreme ultraviolet(EUV)observations are widely used in solar activity research and space weather forecasting since they can observe both the solar eruptions and the source regions of the solar *** field processing is indispensable to remove the instrumental non-uniformity of a solar EUV imager in producing high-quality scientific data from original observed ***-3E(FY-3E)is a meteorological satellite operated in a Sunsynchronous orbit,and the routine EUV imaging data from the Solar X-ray and Extreme Ultraviolet Imager(X-EUVI)onboard FY-3E has the characteristic of concentric *** advantage of the concentric rotation,we propose a post-hoc flat field measurement method for its EUV 195A channel in this *** method removes the small-scale and time-varying component of coronal activities by taking the median value for each pixel along the time axis of a concentric rotation data cube,and then derives the large-scale and invariable component of the quiet coronal radiation,and finally generates a flat field *** flat field can be generated with cadences from hundreds of minutes(one orbit)to several *** flat field accuracy can be achieved by employing more *** analysis shows that our method is able to measure the instrumental spot-like nonuniformity possibly caused by contamination on the detector,which mostly disappears after the in-orbit selfcleaning *** can also measure the quasi-periodic grid-like non-uniformity,possibly from the obscuration of the support mesh on the rear *** flat field correction,these instrumental non-uniformities from the original data are effectively ***,the X-EUVI 195A data after dark and flat field corrections are consistent with the 193A imaging data from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory,verifying the suitability of the *** post-hoc method does not occupy observation time,which is advantageous for space weather operatio

关键词： Sun corona-techniques image processing-methods data analysis-methods observational

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Disturbance impacts of land use change on biodiversity conservation priority areas across China： 1990-2010

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Journal of geographical Sciences 2015年第5期25卷 515-529页

作者： ZHAO Guosong LIU Jiyuan KUANG Wenhui OUYANG Zhiyun XIE Zhenglei Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Re sources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Research center for Eco-Environmental Sciences CAS Beijing 100085 China Key Laboratory of Education Ministry for Poyang Lake Wetland and Watershed Research School of Ge-ography and Environment Jiangxi Normal University Nanchang 330022 China

Land use change is one of the main drivers of biodiversity loss. In the last 20 years, China＇s land use pattern has undergone profound changes. This study constructs an Eco- system Comprehensive Anthropogenic Disturbance Index （ECADI） to assess disturbance impacts of land use change between 1990 and 2010 on biodiversity conservation priority areas at national and regional scales. Four levels of biodiversity conservation areas were categorized： generally important areas, moderately important areas, important areas, and very important areas. The results indicated a higher ECADI value in 2010 in Central and Eastern China than in Western China, and the values of the moderately important, important and very important regions were lower than the average value of the whole country at all levels. Notably, in recent 20 years, the change extent of ECADI values in Central and Eastern China were much greater compared with that in Western China, and ECADI values in the moderately important, important and very important biodiversity conservation areas all showed increasing trends, with the increasing extent lower than that of whole China at all levels. Due to human activities such as urbanization in Eastern China and cropland reclama- tion in Northeast China and Xinjiang, ECADI values showed a medium increase trend （the change rate was about 1%-5% in 10 years）, which indicated the need for more conservation efforts in those regions. However, ECADI values in the Loess Plateau presented a low decline trend （the change rate was about-1% to -0.1% in 10 years） after 2000 because of the ob- vious effectiveness of Green for Grain Project. Furthermore, the variation was negligible in the Tibetan Plateau.

关键词： land use/land cover change farmland reclamation urbanization biodiversity disturbance

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Evaluation of Spirometry for Medical Clearance in Occupations Requiring Respirator Usage

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Occupational Diseases and Environmental Medicine 2017年第3期5卷 67-77页

作者： Ushang Desai Giffe T. Johnson James D. McCluskey Raymond D. Harbison center for Environmental and Occupational Risk analysis and Management College of Public Health University of South Florida Tampa USA

Medical certification of workers for respirator use is an important activity of occupational medicine health professionals. Spirometry is a diagnostic tool to evaluate respiratory distress/insufficiency that may affect respirator use. The pulmonary function data of 337 subjects from different occupations that required medical evaluation to wear a respirator were analyzed to determine the effect of using various spirometric equations on respirator fitness outcomes. Of 337 subjects who were cleared for respiratory use by medical questionnaires for respirator compliance, 14 (4.15%) failed to pass respirator compliance by NFPA criteria and 5 (1.48%) failed to pass respirator compliance measures by ATS criteria. We compared the use of different spirometric equations to evaluate these measures, and it was determined that the Crapo equation cleared more workers for respirator use as compared to the Knudson and NHANES III equations. As some workers were able to qualify for respirator use based on questionnaire alone but failed respirator clearance after pulmonary function testing, it is recommended that spirometry is used to evaluate clearance for all workers who will use a respirator in the workplace. As well, using different spirometric equations can affect the outcome on passing or failing clearance for respirator use, and this should be considered in a respiratory medical certification program.

关键词： Spirometry NHANES III Crapo Knudson Respiratory Protection Program

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A Modified Self-adaptive Method for Mapping Annual 30-m Land Use/Land Cover Using Google Earth Engine:A Case Study of Yangtze River Delta

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Chinese geographical Science 2021年第5期31卷 782-794页

作者： QU Le’an LI Manchun CHEN Zhenjie ZHI Junjun School of Geography and Ocean Science Nanjing UniversityNanjing 210023China School of Geography and Tourism Anhui Normal UniversityAnhui ProvinceWuhu 241002China Jiangsu Provincial Key Laboratory of geographic Information Science and Technology Nanjing UniversityNanjing 210023China

Annual Land Use/Land Cover(LULC)change information at medium spatial resolution(i.e.,at 30 m)is used in applications ranging from land management to achieving sustainable development goals related to food ***,obtaining annual LULC information over large areas and long periods is challenging due to limitations on computational capabilities,training data,and workflow *** the Google Earth Engine(GEE),which provides a catalog of multi-source data and a cloud-based environment,we developed a novel methodology to generate a high accuracy 30-m LULC cover map collection of the Yangtze River Delta by integrating free and public LULC products with Landsat *** major contribution is a hybrid approach that includes three major components:1)a high-quality training dataset derived from multi-source LULC products,filtered by k-means clustering analysis;2)a yearly 39-band stack feature space,utilizing all available Landsat data and DEM data;and 3)a self-adaptive Random Forest(RF)method,introduced for LULC *** results show that our proposed workflow achieves an average classification accuracy of 86.33%in the entire *** results demonstrate the great potential of integrating multi-source LULC products for producing LULC maps of increased *** addition,as the proposed workflow is based on open source data and the GEE cloud platform,it can be used anywhere by anyone in the world.

关键词： Land Use/Land Cover(LULC) self-adaptive Random Forest(RF) Google Earth Engine(GEE) Yangtze River Delta

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The PCK2-glycolysis axis assists three-dimensional-stiffness maintaining stem cell osteogenesis

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Bioactive Materials 2022年第12期7卷 492-506页

作者： Zheng Li Muxin Yue Xuenan Liu Yunsong Liu Longwei Lv Ping Zhang Yongsheng Zhou Department of Prosthodontics Peking University School and Hospital of Stomatology&National Center of Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Research Center of Oral Biomaterials and Digital Medical Devices&Beijing Key Laboratory of Digital Stomatology22 Zhongguancun South AvenueHaidian DistrictBeijing100081PR China

Understanding mechanisms underlying the heterogeneity of multipotent stem cells offers invaluable insights into biogenesis and tissue development. Extracellular matrix (ECM) stiffness has been acknowledged as a crucial factor regulating stem cell fate. However, how cells sense stiffness cues and adapt their metabolism activity is still unknown. Here we report the novel role of mitochondrial phosphoenolpyruvate carboxykinase (PCK2) in enhancing osteogenesis in 3D ECM via glycolysis. We experimentally mimicked the physical characteristics of 3D trabeculae network of normal and osteoporotic bone with different microstructure and stiffness, observing that PCK2 promotes osteogenesis in 3D ECM with tunable stiffness in vitro and in vivo. Mechanistically, PCK2 enhances the rate-limiting metabolic enzyme pallet isoform phosphofructokinase (PFKP) in 3D ECM, and further activates AKT/extracellular signal-regulated kinase 1/2 (ERK1/2) cascades, which directly regulates osteogenic differentiation of MSCs. Collectively, our findings implicate an intricate crosstalk between cell mechanics and metabolism, and provide new perspectives for strategies of osteoporosis.

关键词： Osteogenesis Osteoporosis Extracellular matrix Stiffness PCK2 Mesenchymal stem cells

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Method for Evaluating the Degrees of Land Use Sustainability of Mountainous County and its Application in Yunnan Province,China

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Journal of Mountain Science 2008年第2期5卷 98-112页

作者： YANG Zisheng LIU Yansui TAO Wenxing XU Jingling ZHAO Qiaogui Institute of Land ＆ Resources and Sustainable Development Yunnan University of Finance and Economics Kunming 650221 China Institu te of geographic Sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 China Department of Land ＆ Resources of Yunnan Province Kunming 650224 China

The evaluation of sustainable land use is the key issue in the field of studying the sustainable land utilization. In general analysis, the sustainable land use is evaluated respectively from its ecological sustainability, economic sustainability and social sustainability in China and other countries in recent years. Although this evaluation is an important work, it seems insufficient and hard to comprehensively reflect the whole degree of land use sustainability. Thus, to make up this deficiency, this paper brings forward the evaluation indexes, which make it possible to quantitatively reflect the whole degree of land use sustainability, namely, the concept of "degrees of overall land use sustainability" (DOS), and research and development of the method of measurement and calculation in DOS. Taking the evaluation of the degree of land use sustainability in county regions of Yunnan Province as the actual example for analysis, results are basically as follows:1) The degree of land use sustainability (DOS) is the ration index to organically and systematically integrate the degree of ecological friendliness (DEF), the degree of economic viability (DEV) and the degree of social acceptability (DSA), able to comprehensively reflect the whole sustainability degree of regional land use. 2) Based on the value of DOS, the grading system and standard for the sustainability of land use may be established and totally divided into five grades, namely, the high-degree sustainability, middle-degree sustainability, low-degree sustainability, conditional sustainability and non-sustainability. Meanwhile, the standard for distinguishing sustainability grades has also been confirmed so as to determine the nature of sustainability degrees in different grades. This makes the possibility for the combination of nature determination with ration in research result and provides with the scientific guideline and decision-making gist for better implementation of sustainable land use strategy.3)

关键词：土地利用评价方法生态学经济学

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A method for distinguishing benign and malignant pulmonary nodules based on 3D dual path network aided by K-means clustering analysis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2022年第11期23卷 957-967页

作者： Dachuan GAO Xiaodan YE Xuewen HOU Yang CHEN Xue KONG Yuanzhong XIE Shengdong NIE School of Health Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of Radiology Shanghai Chest HospitalShanghai 200030China Medical Imaging center Tai'an Center HospitalTai'an 271000China

In the USA,there were about 1806590 new cancer cases in 2020,and 606520 cancer deaths are expected to have occurred in *** cancer has become the leading cause of death from cancer in both men and women(Siegel et al.,2020).Clinical studies show that the five-year survival rate of lung cancer patients after early diagnosis and treatment intervention can reach 80%,compared with that of patients having advanced lung ***,the early diagnosis of lung cancer is a key factorto reduce mortality.

关键词： lung diagnosis mortality

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Halogenated Thienoacene Derivatives with Improved Emission Properties

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Chemical Research in Chinese Universities 2024年第4期40卷 699-703页

作者： ZHANG Jingmei MENG Zhihao ZHEN Yonggang HE Ping YU Panpan HU Wenping Advanced Innovation center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic CompositesBeijing University of Chemical TechnologyBeijing100029P.R.China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430074P.R.China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian116024P.R.China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province China West Normal UniversityNanchong637000P.R.China Key Laboratory of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education Jiangxi Normal UniversityNanchang330022P.R.China MOE Key Laboratory of Organic Integrated Circuits&Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of SciencesTianjin UniversityTianjin300072P.R.China

Thienoacenes is one of most important groups of semiconducting materials due to the high stability and superior ***,there are scarce studies on the emission properties of thienoacenes to ***,we synthesized fluorinated and chlorinated dibenzo[d,d’]thieno[3,2-b;4,5-b’]dithiophenes(DBTDTs)derivatives F6-DBTDT and Cl6-DBTDT by sulfoxide cyclization,significantly lowering the energy levels relative to the parent compound *** to single crystal structure analysis,F6-DBTDT molecules adopt one-dimensional slipped stacking with closeπ-πinteractions of 3.43Å(1Å=0.1 nm),which is different from the parent compound DBTDT with herringbone stacking ***,the halogenated DBTDT derivatives exhibit enhanced emission properties both in solution and in the solid state,opening up possiblities to improve photoluminescence of thienoacences by halogenation.

关键词： Thienoacene Halogenation Photoluminescence Aggregation structure

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Numerical simulation of micro-bubble drag reduction of an axisymmetric body using OpenFOAM

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Journal of Hydrodynamics 2019年第5期31卷 900-910页

作者： Xiao-jie Zhao Zhi Zong Yi-chen Jiang Yu Pan School of Naval Architecture Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural analysis for Industrial Equipment Dalian 116024China Collaborative Innovation center for Advanced Ship and Deep-Sea Exploration Dalian 116024China Liaoning Engineering Laboratory for Deep-Sea Floating Structures Dalian 116024China

The two-phase micro-bubble flow over an axisymmetric body is investigated using the OpenFOAM *** numerical model consists of an Eulerian-Eulerian two-fluid model with closure relationships for the interfacial momentum transfer to capture the multiphase flow,a standard A:-￡*model for the continuous phase and one turbulence model inside the OpenFOAM for the dispersed *** bubble sizes are calculated based on the solution of the transport equation of the interfacial area *** simulations in this work are carried out with different air injection rates and different flow *** effects of bubble size on drag reduction are *** numerical results are compared against some available experiments and other numerical *** numerical results indicate that the airflow rate and air volume fraction within the boundary layer near the body play important roles in micro-bubble drag *** frictional drag reduction effect by micro bubbles is larger for lower water speed,and the presence of the micro bubbles can increase the pressure resistance of the *** reduction rates are generally higher when the bubble diameter is smaller.

关键词： Eulerian-Eulerian two-fluid model axisymmetric body micro bubbles drag reduction numerical simulation

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Chemical and behavioral analysis of the cuticular hydrocarbons from Asian citrus psyllid, Diaphorina citri

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Insect Science 2013年第3期20卷 367-378页

作者： Rajinder S. Mann Russell L. Rouseff Jack Smoot Nandikeswara Rao Wendy L. Meyer Stephen L. Lapointe Paul S. Robbins Dong Cha Charles E. Linn Francis X. Webster Siddharth Tiwari Lukasz L. Stelinski Entomology and Nematology Department Citrus Research and Education Center University of Florida Flavor and Volatile analysis Group Citrus Research and Education Center University of Florida Lake Alfred FL 33850 USA National Research center for Citrus Nagpur Maharashtra India USDA-ARS US Horticultural Research Laboratory Fort Pierce FL 34945 Department of Entomology NYS Agricultural Experiment Station Cornell University Geneva NY 14456 Department of Chemistry State University of New York College of Environmental Science and Forestry Syracuse NY 13210 USA

Huanglongbing （HLB） is the most destructive disease of citrus worldwide. The Asian citrus psyllid, Diaphorina citri Kuwayama （Hemiptera： Psyllidae）, is the vector of the phloem-inhabiting bacterium, Candidatus Liberibacter asiaticus, which is presumed to cause HLB in Florida citrus. Laboratory and field studies were conducted to examine the behavioral responses of male and female D. cirri to their cuticular extracts. In olfactometer assays, more male D. citri were attracted to one, five, or 10 female cuticular extract equivalent units than blank controls. The results were confirmed in field studies in which clear or yellow traps baited with 10 female cuticular extract equivalent units attracted proportionately more males than clear traps baited with male cuticular extract or unbaited traps. Analyses of cuticular constituents of male and female D. citri revealed differences between the sexes in chemical composition of their cuticular extracts. Laboratory bioassays with synthetic chemicals identified from cuticular extracts indicated that dodecanoic acid attracted more males than clean air. Traps baited with dodecanoic acid did not increase total catch olD. citri as compared with blank traps at the dosages tested; however, the sex ratio ofpsyllid catch was male biased on traps baited with the highest lure loading dosage tested （10.0 mg）.

关键词： citrus cuticular hydrocarbon dodecanoic acid Huanglongbing semiochemical

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