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Spatial distribution of supra-permafrost groundwater in the Qinghai-Tibet Engineering Corridor using inversion models

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Advances in Climate Change Research 2024年第1期15卷 31-41页

作者： Yu gao ming-Tang CHAI wei MA Yu-Tao gao State Key Laboratory of Frozen Soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China School of Civil and Hydraulic Engineering Ningxia UniversityYinchuan 750021China

Supra-permafrost groundwater(SPG)is a key factor that causes damage to highways and railways in the Qinghai-Tibet Engineering Corridor(QTEC).It is difficult to monitor SPG in the field due to their complex formation mechanisms and movement *** single-site field monitoring studies limit the spatial and temporal precision of SPG spatial *** determine the moisture content of shallow soils and the SPG distribution along the QTEC,this work employed the temperature vegetation dryness index and remote sensing models for groundwater table distribution *** accuracies of the models were validated using mea-surements obtained from different sites in the *** the permafrost zones of the QTEC,72%,22%and 6%of the SPG were located at depths of 0.5-1,1 m,***,79.4%of the area along the Qinghai-Tibet Highway(QTH)(Xidatan-Tanggula)section contained *** these sections with SPG,37.9%have an SPG table at depths of 0.5-0.8 *** study preliminarily explored the SPG distribution in the QTEC with a 30 m *** findings can help improve the spatial scale of SPG research,provide a basis for the analysis of the hydrothermal mechanisms,and serve as a guide in the assessment of operational risks and road structure designs.

关键词： Dryness index Landsat Soil moisture Groundwater level Qinghai-Tibet Engineering Corridor

In Situ Synthesis of Heat Resistant Gradient Composite on Steel Surface

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Journal of Iron and Steel Research International 2009年第2期16卷 89-94页

作者： CUI Xiang-hong WANG Feng WANG Shu-qi YANG Zi-run gao ming-juan wei Min-xian School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 Jiangsu China

A heat resistant gradient composite was synthesized in situ on steel with the self-propagating high temperature synthesis （SHS） reaction of 3Ni-Al-Ti-C system during casting. The phases, microstructure, and composition of the composite were analyzed by using an X-ray diffractometer （XRD）, and a scanning electron microscope （SEM） coupled with an energy-dispersive X-ray spectroscope （EDS）. The formation mechanism of the composite is also discussed. TiC/Ni3 Al/steel gradient composite is achieved by forming the gradient distributions of Fe, Ni, and Al, accompanied with the gradient variation of the microstructure from TiC/Nia A1, to TiC/Ni3 Al/steel, and to steel. The composite is in situ synthesized through whole reaction of 3Ni-Al-Ti-C system in liquid steel and densification procedure, and the liquid steel infiltrates into pores in the SHS product and forces liquid Ni3Al to form self-compaction further.

关键词： steel heat resistant composite synthesis microstructure

CpG Island Definition and Methylation Mapping of the T2T-YAO Genome

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 69-79页

作者： ming Xiao Rui wei Jun Yu Chujie gao Fengyi Yang Le Zhang College of Computer Science Sichuan UniversityChengdu 610065China Key Laboratory of Systems Health Science of Zhejiang Province School of Life ScienceHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Precisely defining and mapping all cytosine(C)positions and their clusters,known as CpG islands(CGIs),as well as their methylation status,are pivotal for genome-wide epigenetic studies,especially when population-centric reference genomes are ready for timely ***,we first align the two high-quality reference genomes,T2T-YAO and T2T-CHM13,from different ethnic backgrounds in a base-by-base fashion and compute their genome-wide density-defined and position-defined ***,by mapping some representative genome-wide methylation data from selected organs onto the two genomes,we find that there are about 4.7%–5.8%sequence divergency of variable categories depending on quality *** among the divergent sequences are mostly associated with neurological ***,CGIs associated with the divergent sequences are significantly different with respect to CpG density and observed CpG/expected CpG(O/E)ratio between the two ***,we find that the T2T-YAO genome not only has a greater CpG coverage than that of the T2T-CHM13 genome when whole-genome bisulfite sequencing(WGBS)data from the European and American populations are mapped to each reference,but also shows more hyper-methylated CpG sites as compared to the T2T-CHM13 *** study suggests that future genome-wide epigenetic studies of the Chinese populations rely on both acquisition of high-quality methylation data and subsequent precision CGI mapping based on the Chinese T2T reference.

关键词： T2T-YAO Position-defined CpG island Density-defined CpG island DNA methylation Genome analysis

Intelligent extraction of road cracks based on vehicle laser point cloud and panoramic sequence images

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Journal of Road Engineering 2024年第1期4卷 69-79页

作者： ming Guo Li Zhu ming Huang Jie Ji Xian Ren Yaxuan wei Chutian gao School of Geomatics and Urban Spatial Informatics Beijing University of Civil Engineering and ArchitectureBeijing 102616China Engineering Research Centre of Representative Building and Architectural Heritage Database Ministry of EducationBeijing 100044China Key Laboratory of Modern Urban Surveying and Mapping National Administration of SurveyingBeijing 102616China School of Civil and Transportation Engineering Beijing University of Civil Engineering and ArchitectureBeijing 102616China

In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road *** methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of *** study employs a vehicle-mounted LiDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence *** extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic ***,a threshold value is set based on the crack elevation change to extract the aligned roadway point *** three-dimensional data pertaining to the cracks can be *** experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road *** utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road *** approach exhibits superior accuracy when compared to conventional ***,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic ***,this technique finds extensive application in the domains of intelligent transportation and urbanization *** technology exhibits significant promise for use in the domains of intelligent transportation and city development.

关键词： Road crack extraction Vehicle laser point cloud Panoramic sequence images Convolutional neural network

Tillage Effect on Organic Carbon in a Purple Paddy Soil

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Pedosphere 2006年第5期16卷 660-667页

作者： HUANG Xue-Xia gao ming wei Chao-Fu XIE De-Ti PAN Gen-Xing College of Resources and Environment Southwest Agricultural University Chongqing 400716 （China） College of Environmental Science and Technology Guangzhou University Guangzhou 510006 （China） College of Resources and Environment Nanjing Agricultural University Nanjing 210095 （China）

The distribution and storage of soil organic carbon (SOC) based on a long-term experiment with various tillage systems were studied in a paddy soil derived from purple soil in Chongqing, China. Organic carbon storage in the 0-20 and 0-40 cm soil layers under different tillage systems were in an order: ridge tillage with rice-rape rotation (RT-rr) > conventional tillage with rice only (CT-r) > ridge tillage with rice only (RT-r) > conventional tillage with rice-rape rotation (CT-rr). The RT-rr system had significantly higher levels of soil organic carbon in the 0-40 cm topsoil, while the proportion of the total remaining organic carbon in the total soil organic carbon in the 0-10 cm layer was greatest in the RT-rr system. This was the reason why the RT-rr system enhanced soil organic carbon storage. These showed that tillage system type was crucial for carbon storage. Carbon levels in soil humus and crop-yield results showed that the RT-rr system enhanced soil fertility and crop productivity. Adoption of this tillage system would be beneficial both for environmental protection and economic development.

关键词： carbon sequestration organic carbon storage purple paddy soil tillage system

Tetraphenylethylene dicycle helicates: circularly polarized luminescence and chiral recognition based on emission wavelength change

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Science China Chemistry 2024年第11期67卷 3817-3824页

作者： Zhi-Rong Xu Miao-Li gao ming Hu wei Yu Yan-Song Zheng Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Chiral tetraphenylethylene(TPE) dicycle tetraaldehyde and TPE dicycle tetraacids bearing optically pure groups on the cycles were designed and synthesized. Due to the propeller-like conformation immobilization of TPE unit, this new class of TPE dicycle was resolved into M-and P-enantiomers, which could emit strong circular polarized luminescence(CPL). Interestingly,these TPE helicates displayed exceptional ability of molecule recognition. While the TPE dicycle tetraaldehyde could detect the microscale water in anhydrous tetrahydrofuran, the chiral TPE dicycle tetraacid could display different fluorescent color after interacting with two enantiomers of a wide variety of chiral amines including monoamines, diamines, and aminols, which could be applied to chiral recognition of these chiral amines. Furthermore, the emission wavelength of TPE dicycle tetraacid was found to change linearly with the enantiomer purity of chiral amine from enantiomer excess(ee) percent-100% to +100%, for the first time showing the potential for quantitative chiral analysis of chiral amines based on emission wavelength change. The emission wavelength was affected less by environmental factors than fluorescence intensity, which would enable the chiral analysis based on wavelength change with higher accuracy and repeatability.

关键词： TPE dicycle helicate CPL chiral recognition enantiomer excess analysis emission wavelength change

OnFractional(g,f,n′,m)-Critical Covered Graphs

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Journal of the Operations Research Society of China 2024年第2期12卷 446-460页

作者： wei gao wei-Fan Wang School of Information Science and Technology Yunnan Normal UniversityKunming 650500YunnanChina Department of Mathematics Zhejiang Normal UniversityJinhua 321004ZhejiangChina

The main contribution in this article is threefold:(1)we show the necessary and sufficient condition for graphs to be fractional(g,f)-covered which can be expressed in different forms,and extended to fractional(g,f,m)-covered graphs;(2)the concept of fractional-critical covered graph is put forward and its necessary and sufficient condition is given;(3)we present the degree condition for a graph to be fractional(g,f,n′,m)-critical covered,and show that degree bound is sharp when m is ***,the related result in fractional(a,b,n′,m)-critical covered setting is also verified.

关键词： Network Fractional factor Data transmission Fractional covered graph Fractional critical covered graph

A novel cascaded H-bridge photovoltaic inverter with flexible arc suppression function

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Global Energy Interconnection 2024年第4期7卷 513-527页

作者： Junyi Tang wei gao College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108P.R.China

This paper presents a novel approach that simultaneously enables photovoltaic(PV)inversion and flexible arc suppression during single-phase grounding *** compensate for ground currents through an arc-elimination function,while outputting a PV direct current(DC)power *** method effectively reduces the residual grounding *** reduce the dependence of the arc-suppression performance on accurate compensation current-injection models,an adaptive fuzzy neural network imitating a sliding mode controller was *** online adaptive adjustment law for network parameters was developed,based on the Lyapunov stability theorem,to improve the robustness of the inverter to fault and connection ***,a new arc-suppression control exit strategy is proposed to allow a zerosequence voltage amplitude to quickly and smoothly track a target value by controlling the nonlinear decrease in current and reducing the regulation *** results showed that the proposed method can effectively achieve fast arc suppression and reduce the fault impact current in single-phase grounding *** to other methods,the proposed method can generate a lower residual grounding current and maintain good arc-suppression performance under different transition resistances and fault locations.

关键词： Photovoltaic inverter Flexible arc suppression Adaptive control Fuzzy neural network Sliding mode control Exit strategy

Inhibition of viability of human retinal microvascular endothelial cells by vialinin A under high glucose condition

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1809-1815页

作者： Zhi-Gang Chen gao-Qin Liu wei-ming Liu Pei-Rong Lu Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Jiangsu Clinical Immunology Institute the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential ***:The HRECs were divided into four groups:normal glucose control group(NG,5 mmol/L D-glucose),high glucose group(HG,30 mmol/L D-glucose),HG+1μmol/L vialinin A group,and HG+5μmol/L vialinin A *** cell viabilities were measured with cell counting kit-8(CCK-8)assay for proliferation,with scratch assay for migration,and tube formation,for evaluation of the impact of vialinin A on cellular ***-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor(VEGF).RESULTS:The proliferative capacity and migration of HRECs was reduced by 5μmol/L vialinin A in high glucose environment(both P<0.05).Vialinin A also inhibited highglucose-induced tube formation of *** expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A(P<0.05).CONCLUSION:Vialinin A inhibits the cell viability of *** may serve as a potential target for anti-angiogenic therapy.

关键词： vialinin A vascular endothelial growth factor human retinal endothelial cells cell viability