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Global cultivated land mapping at 30 m spatial resolution

Science China Earth Sciences 2016年第12期59卷 2275-2284页

作者： cao xin CHEN XueHong ZHANG WeiWei LIAO AnPing CHEN LiJun CHEN ZhiGang CHEN Jin State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University National Geomatics Center of China College of Geomatics Anhui University of Science and Technology

Cultivated land is one of the most important types of land cover in the global mapping of land cover, and its variation influences economic development, food security, and ecological environment protection. Existing products of global cultivated land mapping have a low resolution, and high spatial resolution products are in demand. This study uses global remote sensing image datasets in 2000/2010 with a spatial resolution of 30 m(Landsat TM/ETM+, HJ-1), MODIS 250 m NDVI time-serial data, and many types of reference data. An three-layer extraction method based on pixels, objects, and knowledge(POK) was adopted to ease cultivated land extraction in global-scale 30 m images, i.e., cultivated land classification based on pixel-scale multi-feature optimization, cultivated land automatic identification based on objects, and interactive object processing based on information service and priori knowledge. Global 30 m cultivated land mapping was accomplished for the two reference years(2000 and 2010), and statistical analysis was conducted on the data. Results showed that the total cultivated land area was 1.903 billion ha and 1.960 billion ha, respectively. Accuracy assessments showed that overall accuracy of global cultivated land mapping are higher than 92% for both the two reference years. The global cultivated land products in 2000/2010 developed in this research are superior to their international counterparts in terms of spatial resolution and classification accuracy. They also provide significant basic data on global food security, ecological environment supervision, and global change.

关键词： Cultivated land global 30 m resolution Remote sensing mapping NDVI time series

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Local Lipschitz-α Mappings and Applications to Sublinear Expectations

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Acta Mathematica Sinica,English Series 2014年第5期30卷 844-860页

作者： Huai xin cao Jun Cheng YIN Zhi Hua GUO Zheng Li CHEN College of Mathematics and Information Science Shaanxi Normal University

The aim of this paper is to establish a series of important properties of local Lipschitz-α mappings from a subset of a normed space into a normed space. These mappings include Lipschitz operators, Lipschitz-α opera... 详细信息

关键词： Local Lipschitz-α mapping random variable sublinear expectation

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Measurement of soil water content using ground-penetrating radar: a review of current methods

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International Journal of Digital Earth 2019年第1期12卷 95-118页

作者： xinbo Liu Jin Chen Xihong Cui Qixin Liu xin cao Xuehong Chen State Key Laboratory of Earth Surface Processes and Resource Ecology Institute of Remote Sensing Science and EngineeringFaculty of Geographical ScienceBeijing Normal UniversityBeijingPeople’s Republic of China

Soil water content(SWC)is a crucial parameter in ecology,agriculture,hydrology,and engineering *** on non-invasive monitoring of SWC has been a long-lasting topic in these *** penetrating radar(GPR),a non-destructive geophysical technique,has the advantages of high resolution,deep detection depth,and high efficiency in SWC measurements at medium *** has been successfully applied in field *** paper summarizes the recent progress in developing GPR-based SWC measurement methods,including reflected wave,ground wave,surface reflection,borehole GPR,full waveform inversion,average envelope amplitude,and frequency shift *** principles,advantages,limitations,and applications of these methods are described in detail.A comprehensive technical framework,which comprises the seven methods,is proposed to understand their principles and *** key procedures,namely,data acquisition and data processing,are emphasized as crucial to method *** suitable methods that will satisfy diverse application demands and field conditions are *** development,potential applications,and advances in hardware and data processing techniques are also highlighted.

关键词： Soil water content ground penetrating radar soil permittivity average wave velocity frequency domain analysis

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Modeling tree root diameter and biomass by ground-penetrating radar

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Science China Earth Sciences 2011年第5期54卷 711-719页

作者： CUI XiHong CHEN Jin SHEN JinSong cao xin CHEN XueHong ZHU XiaoLin State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

Roots play a key role in ecosystem functioning as they transfer water and nutrients from soil to plants. Traditional methods for measuring roots are labor-intensive and destructive in nature, which limits quantitative and repeatable assessments in long- term research. Ground-penetrating radar （GPR） provides a non-destructive method to measure plant roots. Based on the superiority of GPR with 2 GHz frequency, we developed a new, practical method to estimate root biomass. First, average root matter density was measured by collecting a small number of root samples. Second, under controlled, experimental conditions in a sandy area, a root diameter estimation model base on GPR was developed from which root diameter was estimated. Third, root volume was calculated using the estimated root diameter and assuming the shape of roots to be cylindrical. Finally, root biomass was estimated by averaging root matter density and root volume. Results of this study suggest the following：（1） the density of coarse roots with diameters greater than 0.5 cm is relatively uniform; （2） a new wave shape parameter, AT, extracted from profile data of 2 GHz frequency antenna is independent of root depth, thus enabling the construction of a root diameter estimation model with high accuracy; and （3） results of a field experiment demonstrated the GPR-based method to be feasible and effective in estimating biomass of coarse roots. These findings are helpful for improving GPR-based root diameter and biomass estimation models and suggest the potential of GPR data in studying root systems.

关键词： ground-penetrating radar tree root system root biomass root diameter

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Relation Between Millimeter Wavelengths Emission and High-Energy Emission for Active Galactic Nuclei

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Chinese Physics Letters 1998年第11期15卷 856-858页

作者： HUANG Li-hua JIANG Dong-rong cao xin-wu Shanghai Observatory Chinese Academy of SciencesShanghai 200030

After comparing the flux densities of a sample of active galactic nuclei detected by energetic gamma-ray experiment telescope at 90 and 230 GHz with theγ-ray emissions detected by Compton Gamma-Ray Observatory and x-ray emission,a strong correlation between the emission at the millimeter wavelength and theγ-ray emission is *** average flux density of x-ray is almost proportional to the average flux density at the millimeter wave-length for quasars detected by energetic gamma-ray experiment telescope,which strongly supports the previous idea that the x-ray emissions of this kind sources are mainly produced by synchrotron self-Compton process.

关键词： process. millimeter Active

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An Interval Maximum Entropy Method for Quadratic Programming Problem

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Journal of China University of Mining and Technology 2005年第4期15卷 379-383页

作者： RUI Wen-juan cao De-xin SONG Xie-wu School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

With the idea of maximum entropy function and penalty function methods, we transform the quadratic programming problem into an unconstrained differentiable optimization problem, discuss the interval extension of the maximum entropy function, provide the region deletion test rules and design an interval maximum entropy algorithm for quadratic programming problem. The convergence of the method is proved and numerical results are presented. Both theoretical and numerical results show that the method is reliable and efficient.

关键词： quadratic programming interval algorithm penalty function maximum entropy function

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葛根素对脂多糖致抑郁模型小鼠行为学及肠道菌群代谢物的作用

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解放军药学学报 2024年第3期37卷 227-234页

作者：曹欣怡叶路芬陈昕桂厚山田姣姣马浩宜春学院化学与生物工程学院江西宜春336000 宜春学院美容医学院江西宜春336000

目的探讨葛根素对脂多糖诱导的小鼠抑郁样行为及其对肠道菌群衍生的短链脂肪酸含量的影响。方法将ICR雄性小鼠随机分为正常对照组、脂多糖模型组、氟西汀(10mg·kg^(-1))组、葛根素低剂量(50mg·kg^(-1))组、葛根素中剂量(100mg·kg^(-... 详细信息

目的探讨葛根素对脂多糖诱导的小鼠抑郁样行为及其对肠道菌群衍生的短链脂肪酸含量的影响。方法将ICR雄性小鼠随机分为正常对照组、脂多糖模型组、氟西汀(10mg·kg^(-1))组、葛根素低剂量(50mg·kg^(-1))组、葛根素中剂量(100mg·kg^(-1))组、葛根素高剂量(200mg·kg^(-1))组,灌胃给药7d。在第7天给药后1h,除正常对照组外,其余各组小鼠腹腔注射脂多糖1mg·kg^(-1)建立小鼠炎性抑郁样模型;24h后以糖水偏好实验、悬尾实验、强迫游泳实验和旷场实验评价其焦虑、抑郁样行为;苏木精和伊红染色检测结肠组织的病理变化;代谢组学检测小鼠粪便中乙酸、丙酸、丁酸、戊酸、异丁酸和异戊酸等短链脂肪酸的含量。结果葛根素中、高剂量组能显著提高小鼠的蔗糖偏嗜度(P<0.01),增加小鼠在旷场实验中的活动距离和站立次数(P<0.01或P<0.05),并显著缩短小鼠在强迫游泳实验和悬尾实验中的不动时间(P<0.01);结肠苏木精和伊红染色结果显示,脂多糖模型小鼠结肠组织损伤,出现明显炎症,经中、高剂量葛根素干预后,能够显著改善小鼠结肠黏膜层损坏,减少炎症。代谢组学分析结果显示,模型组粪便总短链脂肪酸含量显著降低,葛根素高剂量组可显著上调粪便总短链脂肪酸、乙酸、丙酸和丁酸的含量。结论葛根素可改善炎症诱发的小鼠抑郁样症状,提示葛根素的抗抑郁机制可能与调控肠道菌群中短链脂肪酸的含量密切相关。

关键词：葛根素脂多糖肠道菌群短链脂肪酸小鼠

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Ocular injury resulting in eye removal at a large tertiary care center in China

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International Journal of Ophthalmology(English edition) 2020年第8期13卷 1312-1317页

作者： Han Wu Jing-Yi Wang xin-cao Zhong xin Shi Yi-Hua Wu Juan Ye Department of Ophthalmology the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina Department of Toxicology of School of Public Health Zhejiang University School of MedicineHang zhou310029Zhejiang ProvinceChina

AIM:To investigate the risk factors for eye removal following ocular trauma at a major ophthalmology department in ***:A retrospective study of patients who underwent eye removal surgery following ocular trauma was *** outcomes were consulted in detail through the hospital’s computed medical data ***’information including age,gender,cause of ocular trauma,affected eye,and education level was collected and recorded in a standardized ***-squared test,Student’s t-test,Fisher’s exact test,and bivariate correlation analysis were used for statistical ***:The present study included 1675 removal eyes from 1674 patients over the 20-year *** included 80.5%males and 19.5%females,with mean age of *** majority of the patients(70.7%)were blue-collar workers(physical laborers),and 1098 patients(65.6%)did not receive high school ***-related injuries were the most common reason for eye removal(n=739,44.1%),of which 441 cases(59.7%)were related to metal/nail *** most frequent injury type in males was work-related injuries(49.7%),whereas the most frequent injury type in females was home-related injuries(25.8%).CONCLUSION:Work-related injuries are a leading cause of severe ocular injury resulting in eye *** addition,men and undereducated patients are more likely to undergo eye removal surgery following ocular *** study identified multiple high-risk factors leading to eye removal following ocular trauma,which is of great importance for preventing severe eye injuries.

关键词： ocular trauma enucleation evisceration injury types risk factors

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Seaweed pattern formation in the non-axially directional solidification of 2D-like and 3D Al-3 wt.% Mg single crystal

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Journal of Materials Science & Technology 2023年第16期147卷 1-5页

作者： Yumin Wang Bin Yang Shuangming Li xin cao Zhongli Liu Hui xing College of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005China Inner Mongolia Metal Material Research Institute Yantai 264003China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Shaanxi Key Laboratory of Condensed Matter Structure and PropertiesNorthwestern Polytechnical UniversityXi’an 710129China

*** Microstructures are at the centre of materials science and engineering and play an essential role in determining the in-service mechanical properties of metallic alloys[1–4].Extensive theoretical and experimental investigations have been undertaken to describe and determine solidification microstructures as a function of solidification *** seaweed pattern is one of the most important classes of microstructural patterns[5–7].The characteristic of this pattern is that its extending tips—unlike the behaviour observed in needle-like dendrites—split repeatedly into two or more parts.

关键词： solidification pattern directional

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Expeditious and scalable preparation of a Li-Thiele reagent for amine-based bioconjugation

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Chinese Chemical Letters 2021年第2期32卷 700-702页

作者： Jiacheng Li Yuyong Ma Xiang Zhang xin cao Hegui Gong Ang Li Department of Chemistry Shanghai UniversityShanghai 200444China State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences.Shanghai 200032China

Chemoselective amine bioco njugation has long been a challenge for native protein *** by Thiele’s seminal discovery,Li and co-workers recently developed an orto-phthalaldehyde(OPA)based reagent for labeling the amino group of a *** we report an expeditious and scalable synthesis of a Li-Thiele reagent featuring an arene construction *** reagent contains an alkyne side chain as a handle for secondary modification.

关键词： Amine-based bioconjugation Li-Thiele reagent Arene synthesis Ortho-phthalaldehyde

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