High-resolution remote sensing image segmentation is a challenging task. In urban remote sensing, the presenceof occlusions and shadows often results in blurred or invisible object boundaries, thereby increasing the d...High-resolution remote sensing image segmentation is a challenging task. In urban remote sensing, the presenceof occlusions and shadows often results in blurred or invisible object boundaries, thereby increasing the difficultyof segmentation. In this paper, an improved network with a cross-region self-attention mechanism for multi-scalefeatures based onDeepLabv3+is designed to address the difficulties of small object segmentation and blurred targetedge segmentation. First,we use CrossFormer as the backbone feature extraction network to achieve the interactionbetween large- and small-scale features, and establish self-attention associations between features at both large andsmall scales to capture global contextual feature information. Next, an improved atrous spatial pyramid poolingmodule is introduced to establish multi-scale feature maps with large- and small-scale feature associations, andattention vectors are added in the channel direction to enable adaptive adjustment of multi-scale channel features.The proposed networkmodel is validated using the PotsdamandVaihingen datasets. The experimental results showthat, compared with existing techniques, the network model designed in this paper can extract and fuse multiscaleinformation, more clearly extract edge information and small-scale information, and segment boundariesmore smoothly. Experimental results on public datasets demonstrate the superiority of ourmethod compared withseveral state-of-the-art networks.展开更多
The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods.The nozzle-cylinder electrode in the discharge reactor was supplied witha negative nanosecond puls...The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods.The nozzle-cylinder electrode in the discharge reactor was supplied witha negative nanosecond pulsed generator.The optical emission spectrum diagnosis revealed that OH（A2∑＋ → X2Π,306–309 nm）,N32（CΠ→B3Πg,337 nm）,O（3p5p→3s-5s-0,777.2 nm）and O（3p3p→3s3s0,844.6 nm）were produced in the discharge plasma channels.The electron temperature（Te）was calculated from the emission relative intensity ratio between the atomic O 777.2 nm and 844.6 nm,and it increased with the applied voltage and the pulsed frequency and fell within the range of 0.5–0.8 e V.The gas temperature（Tg）that was measured by Lifbase was in a range from 400 K to 600 K.展开更多
Objectives: As a result of global warming, precipitation is likely to increase at certain area (high latitudes). However, the mechanisms that human activity is influenced by global climate change are far from complete...Objectives: As a result of global warming, precipitation is likely to increase at certain area (high latitudes). However, the mechanisms that human activity is influenced by global climate change are far from completely understood. We try to analyze the relationship between industrial emission (trace metal, nitrogen and phosphorus) and climate signature (precipitation) by Chinese industrialization progresses. Methods: Mainly by using the public data from Bulletin of Environment in China, Bulletin of Marine Environmental Status of China and some data of our experiments, we get the analyzed result. Results: Annual average temperature in China after industrialization is significantly increased, whereas annual average precipitation in China after industrialization is no significantly difference. Phytoplankton increases evaporation of seawater and the relative humidity. Phytoplankton biomass will be different in different stages of environmental pollution in coastal areas. The higher relative humidity of Guangzhou (near the second-third class pollution coast-Shenzhen coast with higher phytoplankton biomass) has higher precipitation;in contrast, lower relative humidity of Shanghai (near the inferior fouth class Zhejiang coast) has lower precipitation recent years. Conclusions: Industrial emissions may have two competing effects: one is to promote the growth of phytoplankton and then cause higher seawater evaporation rates and precipitation;another is to decrease water vapour pressure by serious pollution, which then reduces the seawater evaporation rate and precipitation. With temperature increasing, the precipitation is likely to increase only at low pollution area (high latitudes).展开更多
Originating but free from chromosomal DNA,extrachromosomal circular DNAs(eccDNAs)are organized in circular form and have long been found in unicellular and multicellular eukaryotes.Their biogenesis and function are po...Originating but free from chromosomal DNA,extrachromosomal circular DNAs(eccDNAs)are organized in circular form and have long been found in unicellular and multicellular eukaryotes.Their biogenesis and function are poorly understood as they are characterized by sequence homology with linear DNA,for which few detection methods are available.Recent advances in high-throughput sequencing technologies have revealed that eccDNAs play crucial roles in tumor formation,evolution,and drug resistance as well as aging,genomic diversity,and other biological processes,bringing it back to the research hotspot.Several mechanisms of eccDNA formation have been proposed,including the breakage-fusion-bridge(BFB)and translocation-deletion-amplification models.Gynecologic tumors and disorders of embryonic and fetal development are major threats to human reproductive health.The roles of eccDNAs in these pathological processes have been partially elucidated since the first discovery of eccDNA in pig sperm and the double minutes in ovarian cancer ascites.The present review summarized the research history,biogenesis,and currently available detection and analytical methods for eccDNAs and clarified their functions in gynecologic tumors and reproduction.We also proposed the application of eccDNAs as drug targets and liquid biopsy markers for prenatal diagnosis and the early detection,prognosis,and treatment of gynecologic tumors.This review lays theoretical foundations for future investigations into the complex regulatory networks of eccDNAs in vital physiological and pathological processes.展开更多
基金the National Natural Science Foundation of China(Grant Number 62066013)Hainan Provincial Natural Science Foundation of China(Grant Numbers 622RC674 and 2019RC182).
文摘High-resolution remote sensing image segmentation is a challenging task. In urban remote sensing, the presenceof occlusions and shadows often results in blurred or invisible object boundaries, thereby increasing the difficultyof segmentation. In this paper, an improved network with a cross-region self-attention mechanism for multi-scalefeatures based onDeepLabv3+is designed to address the difficulties of small object segmentation and blurred targetedge segmentation. First,we use CrossFormer as the backbone feature extraction network to achieve the interactionbetween large- and small-scale features, and establish self-attention associations between features at both large andsmall scales to capture global contextual feature information. Next, an improved atrous spatial pyramid poolingmodule is introduced to establish multi-scale feature maps with large- and small-scale feature associations, andattention vectors are added in the channel direction to enable adaptive adjustment of multi-scale channel features.The proposed networkmodel is validated using the PotsdamandVaihingen datasets. The experimental results showthat, compared with existing techniques, the network model designed in this paper can extract and fuse multiscaleinformation, more clearly extract edge information and small-scale information, and segment boundariesmore smoothly. Experimental results on public datasets demonstrate the superiority of ourmethod compared withseveral state-of-the-art networks.
基金supported by National Natural Science Foundation of China(Grant No.51207089)
文摘The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods.The nozzle-cylinder electrode in the discharge reactor was supplied witha negative nanosecond pulsed generator.The optical emission spectrum diagnosis revealed that OH（A2∑＋ → X2Π,306–309 nm）,N32（CΠ→B3Πg,337 nm）,O（3p5p→3s-5s-0,777.2 nm）and O（3p3p→3s3s0,844.6 nm）were produced in the discharge plasma channels.The electron temperature（Te）was calculated from the emission relative intensity ratio between the atomic O 777.2 nm and 844.6 nm,and it increased with the applied voltage and the pulsed frequency and fell within the range of 0.5–0.8 e V.The gas temperature（Tg）that was measured by Lifbase was in a range from 400 K to 600 K.
文摘Objectives: As a result of global warming, precipitation is likely to increase at certain area (high latitudes). However, the mechanisms that human activity is influenced by global climate change are far from completely understood. We try to analyze the relationship between industrial emission (trace metal, nitrogen and phosphorus) and climate signature (precipitation) by Chinese industrialization progresses. Methods: Mainly by using the public data from Bulletin of Environment in China, Bulletin of Marine Environmental Status of China and some data of our experiments, we get the analyzed result. Results: Annual average temperature in China after industrialization is significantly increased, whereas annual average precipitation in China after industrialization is no significantly difference. Phytoplankton increases evaporation of seawater and the relative humidity. Phytoplankton biomass will be different in different stages of environmental pollution in coastal areas. The higher relative humidity of Guangzhou (near the second-third class pollution coast-Shenzhen coast with higher phytoplankton biomass) has higher precipitation;in contrast, lower relative humidity of Shanghai (near the inferior fouth class Zhejiang coast) has lower precipitation recent years. Conclusions: Industrial emissions may have two competing effects: one is to promote the growth of phytoplankton and then cause higher seawater evaporation rates and precipitation;another is to decrease water vapour pressure by serious pollution, which then reduces the seawater evaporation rate and precipitation. With temperature increasing, the precipitation is likely to increase only at low pollution area (high latitudes).
基金supported by the National Natural Science Foundation of China [Grant Nos.32170493,32170656]the National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital)[Grant No.BYSYSZKF2022005]the Clinical Medicine Plus X-Young Scholars Project,Peking University,the Fundamental Research Funds for the Central Universities (PKU2023LCXQ036)。
文摘Originating but free from chromosomal DNA,extrachromosomal circular DNAs(eccDNAs)are organized in circular form and have long been found in unicellular and multicellular eukaryotes.Their biogenesis and function are poorly understood as they are characterized by sequence homology with linear DNA,for which few detection methods are available.Recent advances in high-throughput sequencing technologies have revealed that eccDNAs play crucial roles in tumor formation,evolution,and drug resistance as well as aging,genomic diversity,and other biological processes,bringing it back to the research hotspot.Several mechanisms of eccDNA formation have been proposed,including the breakage-fusion-bridge(BFB)and translocation-deletion-amplification models.Gynecologic tumors and disorders of embryonic and fetal development are major threats to human reproductive health.The roles of eccDNAs in these pathological processes have been partially elucidated since the first discovery of eccDNA in pig sperm and the double minutes in ovarian cancer ascites.The present review summarized the research history,biogenesis,and currently available detection and analytical methods for eccDNAs and clarified their functions in gynecologic tumors and reproduction.We also proposed the application of eccDNAs as drug targets and liquid biopsy markers for prenatal diagnosis and the early detection,prognosis,and treatment of gynecologic tumors.This review lays theoretical foundations for future investigations into the complex regulatory networks of eccDNAs in vital physiological and pathological processes.
