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Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China

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Chinese Geographical Science 2024年第3期34卷 548-563页

作者： ZHANG Sumei ZHANG Yuan zhao hongmei College of Mining and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China

The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data.

关键词： crop residue burning burned area Sentinel-2 Multi Spectral Instrument(MSI) logistic regression Songnen Plain,China

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Endothelial phosphodiesterase 4B inactivation ameliorates endothelial-to-mesenchymal transition and pulmonary hypertension

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1726-1741页

作者： Yanjiang Xing Yangfeng Hou Tianfei Fan Ran Gao Xiaohang Feng Bolun Li Junling Pang Wenjun Guo Ting Shu Jinqiu Li Jie Yang Qilong Mao Ya Luo Xianmei Qi Peiran Yang Chaoyang Liang hongmei zhao Wenhui Chen Jing Wang Chen Wang State Key Laboratory of Respiratory Health and Multimorbidity Institute of Basic Medical SciencesChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100005China Department of Lung Transplantation National Center for Respiratory MedicineNational Clinical Research Center for Respiratory DiseasesChina–Japan Friendship HospitalInstitute of Respiratory MedicineChinese Academy of Medical SciencesBeijing 100029China Haihe Laboratory of Cell Ecosystem Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300051China The State Key Laboratory of Complex Severeand Rare DiseasesInstitute of Basic Medical SciencesChinese Academy of Medical SciencesDepartment of PathophysiologyPeking Union Medical CollegeBeijing 100005China Department of Pharmacy West China HospitalSichuan UniversityChengdu 610044China

Pulmonary hypertension (PH) is a fatal disorder characterized by pulmonary vascular remodeling and obstruction. The phosphodiesterase 4 (PDE4) family hydrolyzes cyclic AMP (cAMP) and is comprised of four subtypes (PDE4A–D). Previous studies have shown the beneficial effects of pan-PDE4 inhibitors in rodent PH;however, this class of drugs is associated with side effects owing to the broad inhibition of all four PDE4 isozymes. Here, we demonstrate that PDE4B is the predominant PDE isozyme in lungs and that it was upregulated in rodent and human PH lung tissues. We also confirmed that PDE4B is mainly expressed in the lung endothelial cells (ECs). Evaluation of PH in Pde4b wild type and knockout mice confirmed that Pde4b is important for the vascular remodeling associated with PH. In vivo EC lineage tracing demonstrated that Pde4b induces PH development by driving endothelial-to-mesenchymal transition (EndMT), and mechanistic studies showed that Pde4b regulates EndMT by antagonizing the cAMP-dependent PKA–CREB–BMPRII axis. Finally, treating PH rats with a PDE4B-specific inhibitor validated that PDE4B inhibition has a significant pharmacological effect in the alleviation of PH. Collectively, our findings indicate a critical role for PDE4B in EndMT and PH, prompting further studies of PDE4B-specific inhibitors as a therapeutic strategy for PH.

关键词： Phosphodiesterase 4B Pulmonary hypertension Endothelial-to-mesenchymal transition

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法律鼓励帮助子女等家庭成员亲身陪伴照护老年人--背景、涵义、法理与制度

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社会科学战线 2024年第1期 187-197页

作者：赵红梅中国政法大学民商经济法学院北京100088

传统孝老文化在现当代遭遇了前所未有的巨大挑战,现当代孝老文化较之传统孝老文化内涵发生了深刻变化--偏重具有精神慰藉功能的亲身陪伴照护。子女等家庭成员亲身陪伴照护老年人存在现实障碍,法律对此应当予以鼓励帮助而非强制。我国可... 详细信息

传统孝老文化在现当代遭遇了前所未有的巨大挑战,现当代孝老文化较之传统孝老文化内涵发生了深刻变化--偏重具有精神慰藉功能的亲身陪伴照护。子女等家庭成员亲身陪伴照护老年人存在现实障碍,法律对此应当予以鼓励帮助而非强制。我国可借鉴域外经验并突出本土特色,从财政补贴及失能长期照护保险、税费减免、保障性住房供应方面进行制度构建。

关键词：子女家庭成员亲身陪伴照护老年人法律鼓励帮助

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Research on Cross-Cultural Communication from the Perspective of Multiculturalism

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学术界 2020年第9期 219-226页

作者： zhao hongmei School of Foreign Languages Chongqing University of Technology Chongqing 400054

With the development of globalization,international exchanges in politics,economy and culture have become increasingly frequent.Accordingly,it is quite necessary and imperious for us to understand other cultures and improve cross-cultural communicative competence.This essay aims to probe into the forms and characteristics of cross-cultural communication from the perspective of multiculturalism,and explore the strategies on how to achieve proper and effective cross-cultural communication.

关键词： culture multiculturalism communication cross-cultural communication cross-cultural communicative competence

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A High Resolution Emission Inventory of Domestic Burning in Rural Region of Northeast China Based on Household Consumption

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Chinese Geographical Science 2020年第5期30卷 921-933页

作者： zhao hongmei YANG Guangyi XIU Aijun ZHANG Xuelei Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of Sci-encesChangchun 130102China University of Chinese Academy of Science Bejing 100049China

Domestic burning emits large amounts of pollutants into the ambient air due to incomplete and inefficient combustion, with significant impacts on indoor air quality and human health. Northeast China is one of the major contributors to domestic burning emissions in China;however, the high-resolution emissions inventories of domestic biomass and coal burning in Northeast China are lacked, which are needed to estimate the extent of its impact. In this study, we established a town-level emissions inventory of gaseous pollutants and particulate matter(PM) from domestic biomass and coal burning, based on per household consumption in each town in rural region of Northeast China. The results revealed that biomass burning was the major domestic burning source over the region in 2016. Domestic biomass burning is the major contributor to PM and volatile organic compounds(VOCs) emissions, while coal burning is the major contributor to SO2 emissions. High emissions intensities were concentrated around the cities of Harbin, Suihua, Changchun, Qiqihar, and Chifeng, each with emissions intensity for PM2.5 and VOCs of more than 2000 Mg per 27 km × 27 km grid cell. Additionally, there are three burning peaks(6-7 am, 12 pm and 4-7 pm) during both the heating(from October to April) and non-heating seasons(from May to September), due to cooking and heating. The burning peaks in the non-heating season were more notable than those in the heating season. These results suggest that the government should pay more attention to domestic biomass and coal burning in rural areas, in order to reduce pollutant emissions and control regional haze during the heating season.

关键词： residential emission particulate matter(PM) source contribution indoor air pollution spatiotemporal distribution

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裸露与沙埋对极端干旱区凋落物分解和养分释放的影响

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干旱区研究 2024年第2期41卷 293-300页

作者：袁萍韩欢赵红梅李从娟新疆农业大学资源与环境学院新疆乌鲁木齐830052 中国科学院新疆生态与地理研究所国家荒漠-绿洲生态建设工程技术研究中心新疆乌鲁木齐830011 中国科学院大学北京100049 新疆土壤与植物生态过程实验室新疆乌鲁木齐830052

为了评估沙漠公路防护林林带裸露与沙埋处理下的凋落物分解和养分动态特征,以梭梭(Haloxylon ammodendron)和乔木状沙拐枣(Calligonum arborescens)同化枝、多枝柽柳(Tamarix ramosissima)叶凋落物为研究对象,用凋落物分解袋法进行分解... 详细信息

为了评估沙漠公路防护林林带裸露与沙埋处理下的凋落物分解和养分动态特征,以梭梭(Haloxylon ammodendron)和乔木状沙拐枣(Calligonum arborescens)同化枝、多枝柽柳(Tamarix ramosissima)叶凋落物为研究对象,用凋落物分解袋法进行分解试验。结果表明:(1)3种凋落物的质量损失在2种处理下均存在显著差异,沙埋处理下凋落物质量损失大于裸露处理,至分解试验结束,裸露处理下梭梭、乔木状沙拐枣和多枝柽柳的失重率分别为7%、6.8%、18.1%;沙埋处理下梭梭、乔木状沙拐枣和多枝柽柳的失重率分别为23.7%、9.7%、21.9%;(2)分解过程中,2种处理下凋落物C、N、P含量变化不太一致,梭梭与乔木状沙拐枣同化枝的N与P含量均呈净富集状态,而C含量则呈现净释放状态;多枝柽柳叶的N和P含量分别呈净富集、净释放状态,C含量为富集-释放状态;(3)分解速率k值与相关因素分析表明,凋落物初始N、P、C:N与C:P含量对分解速率影响显著(P<0.01)。这些结果说明,在极端干旱区,沙埋对凋落物的分解过程有显著的积极影响。

关键词：极端干旱区凋落物分解沙埋质量残留率

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Changes of Precipitation Infiltration Recharge in the Circumstances of Coal Mining Subsidence in the Shen-Dong Coal Field,China

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Acta Geologica Sinica(English Edition) 2012年第4期86卷 993-1003页

作者： ZHANG Fawang SONG Yaxin zhao hongmei HAN Zhantao WANG Dong Institute of Hydrogeology and Environmental Geology CAGS Institute of Karst Geology CAGS/Karst Dynamics LaboratoryMinistry of Land and Resources Non-ferrous Metal Geological Survey Center

Coal mining subsidence is a universal environmental-geological problem in mining areas. By selecting the Shen-Dong coal mining subsidence area as the research field, this paper studies the changes in precipitation infiltration recharge in the circumstances of coal mining subsidence by means of field geological investigation and laboratory simulation experiments, which is expected to provide a scientific basis for eco-environmental restoration in the mining area. The results indicate that at the unstable stage of subsidence, three types of subsidence in the Shen-Dong mining area have positive effects on the precipitation infiltration recharge, and the type of full-thickness bedrock subsidence has the greatest influence. In the stable stage of subsidence, the precipitation infiltration process after long- term drought and the moisture migration in the aeration zone undergo three different stages： evaporation-infiltration before precipitation, infiltration-upward infiltration-infiltration during precipitation and evaporation-infiltration after precipitation. During a heavy rainfall infiltration process, the wetting front movement in fine sand, coarse sand and dualistic structure of fine-coarse sand consists of two stages： the stage of wetting front movement during precipitation, in which the wetting front movement distance has linear relationship with the depth, and the stage of wetting front movement after precipitation, in which the wetting front movement distance has the power function relationship with the depth. The wetting front movement velocity is influenced by the rainfall amount and the lithology in the aeration zone. However, as the depth increases, the movement velocity will decay exponentially.

关键词： precipitation infiltration simulation coal mining subsidence Shen-Dong mining area

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Optimization of air quantity regulation in mine ventilation networks using the improved differential evolution algorithm and critical path method

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International Journal of Mining Science and Technology 2015年第1期25卷 79-84页

作者： Chen Kaiyan Si Junhong Zhou Fubao Zhang Renwei Shao He zhao hongmei Faculty of Safety Engineering China University of Mining & Technology Shaanxi Coal and Chemical Technology Institute Co. Ltd.

In mine ventilation networks, the reasonable airflow distribution is very important for the production safety and economy. Three basic problems of the natural, full-controlled and semi-controlled splitting were reviewed in the paper. Aiming at the high difficulty semi-controlled splitting problem, the general nonlinear multi-objectives optimization mathematical model with constraints was established based on the theory of mine ventilation networks. A new algorithm, which combined the improved differential evaluation and the critical path method(CPM) based on the multivariable separate solution strategy,was put forward to search for the global optimal solution more efficiently. In each step of evolution,the feasible solutions of air quantity distribution are firstly produced by the improved differential evolution algorithm, and then the optimal solutions of regulator pressure drop are obtained by the CPM.Through finite steps iterations, the optimal solution can be given. In this new algorithm, the population of feasible solutions were sorted and grouped for enhancing the global search ability and the individuals in general group were randomly initialized for keeping diversity. Meanwhile, the individual neighborhood in the fine group which may be closely to the optimal solutions were searched locally and slightly for achieving a balance between global searching and local searching, thus improving the convergence rate. The computer program was developed based on this method. Finally, the two ventilation networks with single-fan and multi-fans were solved. The results show that this algorithm has advantages of high effectiveness, fast convergence, good robustness and flexibility. This computer program could be used to solve large-scale generalized ventilation networks optimization problem in the future.

关键词：差分进化算法矿井通风网络关键路径法网络优化风量调节全局搜索能力非线性多目标优化全局最优解

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Freeze-thaw Effects on Sorption/Desorption of Dissolved Organic Carbon in Wetland Soils

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Chinese Geographical Science 2010年第3期20卷 209-217页

作者： YU Xiaofei ZHANG Yuxia zhao hongmei LU Xianguo WANG Guoping Northeast Institute of Geography and Agroeeology Chinese Academy of Sciences Changehun 130012 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The effects of freeze-thaw cycles on sorption/desorption of dissolved organic carbon (DOC) in two wetland soils and one reclaimed wetland soil were investigated. DOC concentrations added were 0-600 mg/L. Laboratory incubations of sorption/desorption of DOC had been carried out at -15℃ for 10 h, and then at +5℃ for 13 h. Soil samples were refrozen and thawed subsequently for 5 cycles. Initial Mass model was used to describe sorption behavior of DOC. The results indicate that freeze-thaw cycles can significantly increase the sorption capacity of DOC and reduce the desorption capacity of DOC in the three soils. The freeze-thaw effects on desorption of DOC in soils increase with the increasing freeze-thaw cycles. The conversion of natural wetlands to soybean farmland can decrease the sorption capacity and increase the desorption capacity of DOC in soils. Global warming and reclamation may increase DOC release, and subsequently increase the loss of carbon and the emission of greenhouse gas.

关键词：溶解有机碳湿地土壤冻融循环吸附行为脱附吸附能力解吸能力 DOC

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Water-use efficiency in response to simulated increasing precipitation in a temperate desert ecosystem of Xinjiang, China

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Journal of Arid Land 2017年第6期9卷 823-836页

作者： HUANG Gang LI Yan MU Xiaohan zhao hongmei CAO Yanfeng State Key Lab of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Xinjiang Key Laboratory of Soil and Plant Ecological Processes College of Grassland and Environmental Sciences Xinjiang Agricultural University Geology Science Department Shannxi Normal University

Water-use efficiency（WUE） is a key plant functional trait that plays a central role in the global cycles of water and carbon. Although increasing precipitation may cause vegetation changes, few studies have explored the linkage between alteration in vegetation and WUE. Here, we analyzed the responses of leaf WUE, ecosystem carbon and water exchanges, ecosystem WUE, and plant community composition changes under normal conditions and also under extra 15% or 30% increases in annual precipitation in a temperate desert ecosystem of Xinjiang, China. We found that leaf WUE and ecosystem WUE showed inconsistent responses to increasing precipitation. Leaf WUE consistently decreased as precipitation increased. By contrast, the responses of the ecosystem WUE to increasing precipitation are different in different precipitation regimes： increasing by 33.9% in the wet year（i.e., the normal precipitation years）and decreasing by 4.1% in the dry year when the precipitation was about 30% less than that in the wet year.We systematically assessed the herbaceous community dynamics, community composition, and vegetation coverage to explain the responses of ecosystem WUE, and found that the between-year discrepancy in ecosystem WUE was consistent with the extent to which plant biomass was stimulated by the increase in precipitation. Although there was no change in the relative significance of ephemerals in the plant community, its greater overall plant biomass drove an increased ecosystem WUE under the conditions of increasing precipitation in 2011. However, the slight increase in plant biomass exerted no significant effect on ecosystem WUE in 2012. Our findings suggest that an alteration in the dominant species in this plant community can induce a shift in the carbon-and water-based economics of desert ecosystems.

关键词： desert ecosystem ecosystem water-use efficiency gross carbon exchange increasing precipitation leaf water-use efficiency net carbon exchange Gurbantunggut Desert

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