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Effect of exposure to ambient PM2.5 pollution on the risk of respiratory tract diseases: a meta-analysis of cohort studies 被引量:17
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作者 Qian Liu Cheng Xu +5 位作者 Guixiang Ji Hui Liu Wentao Shao Chunlan Zhang Aihua Gu Peng Zhao 《The Journal of Biomedical Research》 CAS CSCD 2017年第2期130-142,共13页
The International Agency for Research on Cancer and the World Health Organization have designated airborne particulates, including particulates of median aerodynamic diameter 〈 2.5 gm (PM2.5), as Group 1 carcinogen... The International Agency for Research on Cancer and the World Health Organization have designated airborne particulates, including particulates of median aerodynamic diameter 〈 2.5 gm (PM2.5), as Group 1 carcinogens. It has not been determined, however, whether exposure to ambient PM2.5 is associated with an increase in respiratory related diseases. This meta-analysis assessed the association between exposure to ambient fine particulate matter (PM2.5) and the risk of respiratory tract diseases, using relevant articles extracted from PubMed, Web of Science, and Embase. In results, of the 1,126 articles originally identified, 35 (3.1%) were included in this meta-analysis. PM2.5 was found to be associated with respiratory tract diseases. After subdivision by age group, respiratory tract disease, and continent, PM2.5 was strongly associated with respiratory tract diseases in children, in persons with cough, lower respiratory illness, and wheezing, and in individuals from North America, Europe, and Asia. The risk of respiratory tract diseases was greater for exposure to traffic-related than non-traffic-related air pollution. In children, the pooled relative risk (RR) represented significant increases in wheezing (8.2%), cough (7.5%), and lower respiratory illness (15.3%). The pooled RRs in children were 1.091 (95%CI: 1.049, 1.135) for exposure to 〈 25 gg/m3 PM2.5, and 1.126 (95%CI: 1.067, l. 190) for exposure to 〉 25 gg/m3 PM2.5. In conclusion, exposure to ambient PM2.5 was significantly associated with the development of respiratory tract diseases, especially in children exposed to high concentrations of PM2.5. 展开更多
关键词 particulate matter pm2.5 respiratory tract disease META-ANALYSIS cohort study
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Spatiotemporal Patterns of Urban PM2.5 Pollution in China
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作者 LU Debin YANG Dongyang 《Journal of Landscape Research》 2020年第5期34-41,46,共9页
Air pollution is one of the top environmental concerns and causes of deaths and variousdiseases worldwide. In this paper, PM2.5 observation data at 1,497 automatic air quality-monitoringstations in 367 cities of China... Air pollution is one of the top environmental concerns and causes of deaths and variousdiseases worldwide. In this paper, PM2.5 observation data at 1,497 automatic air quality-monitoringstations in 367 cities of China in 2015 were utilized, and the study on spatiotemporal distribution of PM2.5concentration found that the average annual concentration of PM2.5 in urban China in 2015 was 49.74 μg/m3and exceeded the annual average limit in 287 cities. PM2.5 concentrations were highest in winter and lowestin summer in most cities, but it reached the highest in spring in the cities around Taklimakan Desert. Therewere 320 fi ne days in 2015 and the maximum PM2.5 was prone to appear at night, the minimum was usuallyin the afternoon, but in the early morning in Lhasa, and the minimum in winter was even in the earlymorning, midday and afternoon in some cities. Higher concentrations of PM2.5 were found in the EastChina Plain and the cities around Taklimakan Desert, preceded by the Yangtze River Delta economic zone,Chengdu-Chongqing economic zone and Harbin-Changchun megalopolis, while the lower values coveredthe northwestern region of Xinjiang, Heilongjiang Xing’an Mountains region, northeast high latitudes ofInner Mongolia, southwest high altitudes in the border area of Sichuan, Yunnan, Qinghai-Tibet Plateau andthe southeast coastal areas. 展开更多
关键词 pm2.5 Air pollution Spatiotemporal patterns
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地区空气污染的“压力”与企业绿色转型的“动力”——基于城市PM2.5和公司并购的实证发现 被引量:2
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作者 蔡庆丰 舒少文 黄蕾 《厦门大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第1期50-63,共14页
地区空气污染会影响域内各类市场主体行为,包括微观企业决策。碳达峰、碳中和的提出要求各地加强空气污染治理,推动企业绿色转型,而绿色并购是企业绿色转型的重要方式。利用2013—2018年我国A股上市的污染企业发起的并购为样本,并手动... 地区空气污染会影响域内各类市场主体行为,包括微观企业决策。碳达峰、碳中和的提出要求各地加强空气污染治理,推动企业绿色转型,而绿色并购是企业绿色转型的重要方式。利用2013—2018年我国A股上市的污染企业发起的并购为样本,并手动搜集整理确定绿色并购样本,实证研究地区空气污染对域内企业绿色转型的影响。研究发现,地区空气污染加剧会提升域内污染企业绿色并购的意愿。在此基础上,通过并购前后企业信息披露质量和社会责任承担变化,研究发现地区空气污染加剧下的企业绿色转型并非源于自主绿色转型发展的内生“动力”,更多是外部“压力”下的“工具主义”行为。从影响路径来看,地区空气污染引致的压力会通过行业竞争和融资约束这两个途径影响污染企业绿色转型的“动力”。最后,异质性检验发现在市场化程度高和非国有企业样本,地区空气污染加剧对企业绿色并购的促进作用更为显著。 展开更多
关键词 地区空气污染 绿色转型 公司并购 pm2.5
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Rapid improvement of PM2.5 pollution and associated health benefits in China during 2013–2017 被引量:25
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作者 Tao XUE Jun LIU +9 位作者 Qiang ZHANG Guannan GENG Yixuan ZHENG Dan TONG Zhu LIU Dabo GUAN Yu BO Tong ZHU Kebin HE Jiming HAO 《Science China Earth Sciences》 SCIE EI CAS CSCD 2019年第12期1847-1856,共10页
Exposure to fine particulate matter(PM2.5)is known to harm public health.In China,after implementation of aggressive emissions control measures under the Action Plan of Air Pollution Prevention and Control(2013-2017),... Exposure to fine particulate matter(PM2.5)is known to harm public health.In China,after implementation of aggressive emissions control measures under the Action Plan of Air Pollution Prevention and Control(2013-2017),air quality has significantly improved.In this work,we investigated changes in PM2.5 exposure and the associated health impacts in China for the period 2013-2017.We used an optimal estimator of PM2.5 combining in-situ observations,satellite measurements,and simulations from a chemical transport model to derive the spatial and temporal variations in PM2.5 exposure,and then used welldeveloped exposure-response functions to estimate the premature deaths attributable to PM2.5 exposure.We found that national population-weighed annual mean PM2.5 concentrations decreased from 67.4μgm-3 in 2013 to 45.5μgm-3 in 2017(32%reduction).This rapid decrease in PM2.5 pollution led to a 14%reduction in premature deaths due to long-term exposure.We estimated that,during 2013-2017,the premature deaths attributable to long-term PM2.5 exposure decreased from 1.2 million(95%CI:1.0,1.3;fraction of total mortality:13%)in 2013 to 1.0 million(95%CI:0.9,1.2;10%)in 2017.Despite the rapid decrease in annual mean PM2.5 concentrations,health benefits associated with reduced long-term exposure were limited,because for many cities,the PM2.5 levels remain at the portion where the exposure-response function is less steeper than that at the lowconcentration end.We also found that the deaths associated with acute exposure decreased by 61%during 2013-2017 due to rapid reduction in the number of heavily polluted days.Our results confirm that clean air policies in China have mitigated the air pollution crisis;however,continuous emissions reduction efforts are required to protect citizens from air pollution. 展开更多
关键词 AIR quality IMPROVEMENT Health impact assessment Action PLAN of AIR pollution prevention and control pm2.5 MORTALITY
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Dominant Synoptic Patterns and Their Relationships with PM2.5 Pollution in Winter over the Beijing–Tianjin–Hebei and Yangtze River Delta Regions in China 被引量:5
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作者 Yuzhi LIU Bing WANG +3 位作者 Qingzhe ZHU Run LUO Chuqiao WU Rui JIA 《Journal of Meteorological Research》 SCIE CSCD 2019年第4期765-776,共12页
This paper concerns about the episodes of PM2.5 pollution that frequently occur in China in winter months.The severity of PM2.5 pollution is strongly dependent on the synoptic-scale atmospheric conditions.We combined ... This paper concerns about the episodes of PM2.5 pollution that frequently occur in China in winter months.The severity of PM2.5 pollution is strongly dependent on the synoptic-scale atmospheric conditions.We combined PM2.5 concentration data and meteorological data with the Hybrid Single Particle Lagrangian Integrated Trajectory model(HYSPLIT4)to investigate the dominant synoptic patterns and their relationships with PM2.5 pollution over the Beijing–Tianjin–Hebei(BTH)and Yangtze River Delta(YRD)regions in the winters of 2014–17.The transport of PM2.5 from the BTH to YRD regions was examined by using cluster analysis and HYSPLIT4.It is found that the level of PM2.5 pollution over the BTH region was higher than that over the YRD region.The concentration of PM2.5 in the atmosphere was more closely related to meteorological factors over the BTH region.The episodes of PM2.5 pollution over the BTH region in winter were related to weather patterns such as the rear of a high-pressure system approaching the sea,a high-pressure field,a saddle pressure field,and the leading edge of a cold front.By contrast,PM2.5 pollution episodes in the YRD region in winter were mainly associated with the external transport of cold air,a high-pressure field,and a uniform pressure field.Cluster analysis shows that the trajectories of PM2.5 were significantly different under different weather patterns.PM2.5 would be transported from the BTH to the YRD within 48 h when the PM2.5 pollution episodes were associated with three different kinds of weather patterns:the rear of a highpressure system approaching the sea,the high-pressure field,and the leading edge of a cold front over the BTH region.This suggests a possible method to predict PM2.5 pollution episodes based on synoptic-scale patterns. 展开更多
关键词 pm2.5 pollution EPISODES SYNOPTIC patterns BEIJING-TIANJIN-HEBEI (BTH) Yangtze River Delta (YRD)
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Effects of Imports and Exports on China's PM2.5 Pollution 被引量:2
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作者 Zhaohua Li Ziwei Fang Zhuyu Tang 《China & World Economy》 SCIE 2020年第6期28-50,共23页
This paper examines the effects o f imports and exports on Chinas PM2.5 pollution using data from 31 provinces during the period 2001-2016.At the aggregate level,our analysis shows that exports have a pollution-genera... This paper examines the effects o f imports and exports on Chinas PM2.5 pollution using data from 31 provinces during the period 2001-2016.At the aggregate level,our analysis shows that exports have a pollution-generating effect while imports have a pollution-shifting effect on provincial PM2.5 pollution.Cross-sectional analysis reveals that imports and exports exhibit opposite effects on manufacturing and high-tech industries,but demonstrate the same pollution-generating effect for the heavy industry sector.At the regional level,the effects are similar to those at the aggregate level.We also examine the impacts o f other factors on PM2.5 pollution.Our empirical evidence shows that PM2.5 pollution is positively correlated with domestic sales,population density,economic growth,urbanization rate,and transportation,but negatively correlated with energy efficiency and industry structure.This paper suggests that reducing exports and increasing imports will help to reduce PM2.5 pollution. 展开更多
关键词 import and export pm2.5 pollution-generating effect pollution-shifting effect
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基于UPLC-Q-TOF MS的染毒(PM2.5)大鼠尿液代谢组学研究 被引量:1
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作者 鲁婷婷 秦鹏 +3 位作者 薛慧铭 冯真 罗旭萍 郑梅竹 《分析测试学报》 CAS CSCD 北大核心 2024年第8期1294-1300,共7页
为探明PM2.5对大鼠代谢组学的影响,将SD大鼠随机分为对照组(SC)和PM2.5模型组(MG),每组15只。将生理盐水和PM2.5混悬液分别注入各组大鼠气管,每周2次,持续4周。通过超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF MS)对各组大鼠尿液的... 为探明PM2.5对大鼠代谢组学的影响,将SD大鼠随机分为对照组(SC)和PM2.5模型组(MG),每组15只。将生理盐水和PM2.5混悬液分别注入各组大鼠气管,每周2次,持续4周。通过超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF MS)对各组大鼠尿液的代谢组学变化进行检测,采用多元统计分析探究整体代谢组学的变化。通过数据分析和数据库检索,从大鼠尿样中鉴定出17种潜在生物标记物,主要代谢途径涉及戊糖和葡萄糖醛酸相互转化、色氨酸代谢、酪氨酸代谢、苯丙氨酸代谢、嘌呤代谢、对乙酰氨基酚代谢、视黄醇代谢和丙戊酸代谢途径,PM2.5对大鼠诱导损伤作用,可能与其扰乱大鼠体内正常代谢活动有关。研究结果有助于了解PM2.5的毒理学机制,筛选PM2.5暴露大鼠的潜在生物标志物,为进一步探索PM2.5毒性作用及致病机制提供了理论依据。 展开更多
关键词 超高效液相色谱-四极杆-飞行时间质谱 pm2.5 代谢组学 尿液
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PM2.5诱导NLRP3炎症小体活化对人主动脉内皮细胞的影响
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作者 南凯 张俊芳 +4 位作者 梁爽 张辉 李海涛 王芳 姚春霞 《河北医药》 CAS 2024年第15期2266-2270,共5页
目的 探讨PM2.5诱导人主动脉内皮细胞(HAECs)损伤的分子机制。方法 收集大气PM2.5染毒HAECs 24 h,采用MTT法检测细胞存活率,酶联免疫吸附实验检测(ELISA)白介素-1β(IL-1β)和IL-18的含量,硫代巴比妥法检测丙二醛(MDA)含量,比色法检测... 目的 探讨PM2.5诱导人主动脉内皮细胞(HAECs)损伤的分子机制。方法 收集大气PM2.5染毒HAECs 24 h,采用MTT法检测细胞存活率,酶联免疫吸附实验检测(ELISA)白介素-1β(IL-1β)和IL-18的含量,硫代巴比妥法检测丙二醛(MDA)含量,比色法检测乳酸脱氢酶(LDH)活性,Western blot和Q-PCR法检测NLRP3、caspase-1、IL-1β、Bax和Bcl-2的表达,流式细胞术和DAPI染色检测细胞凋亡,活性氧(ROS)和线粒体ROS(mtROS)试剂盒检测ROS和mtROS水平,使用NLRP3 siRNA及ROS和mtROS特异性抑制剂(NAC和Mito-TEMPO)后,观察上述结果的变化。结果 PM2.5可引起HAECs细胞分泌IL-1β和IL-18增加,释放MDA和LDH增多,促进细胞凋亡,并呈现剂量依赖关系;PM2.5可诱导HAECs细胞caspase-1和IL-1β表达增加,还可使HAECs细胞的ROS和mtROS水平显著升高;使用NLRP3 siRNA以及ROS和mtROS的抑制剂可明显抑制上述效应。结论 PM2.5通过诱导HAECs细胞氧化应激而活化NLRP3炎症小体,进一步引起细胞炎性反应和凋亡。 展开更多
关键词 pm2.5 NLRP3炎症小体 人主动脉内皮细胞 氧化应激 细胞凋亡
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保肺化纤方调控TGF-β1/smad2/3、Wnt1/β-catenin信号通路对BLM/PM2.5诱导的特发性肺纤维化大鼠肺组织胶原沉积的影响
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作者 马宁怡 千孟丹 +5 位作者 何慧慧 刘学芳 冯素香 刘素晓 林珊珊 李亚 《辽宁中医杂志》 CAS 北大核心 2024年第9期191-195,I0005,共6页
目的探讨保肺化纤方经转化生长因子(transforming growth factor,TGF)-β1/smad2/3、Wnt1/β-连环蛋白(catenin)信号通路减轻博来霉素(bleomycin,BLM)/PM2.5暴露诱导的特发性肺纤维化(idiopathic pulmonary fibrosis,IPF)大鼠肺组织胶... 目的探讨保肺化纤方经转化生长因子(transforming growth factor,TGF)-β1/smad2/3、Wnt1/β-连环蛋白(catenin)信号通路减轻博来霉素(bleomycin,BLM)/PM2.5暴露诱导的特发性肺纤维化(idiopathic pulmonary fibrosis,IPF)大鼠肺组织胶原沉积的作用机制。方法SD大鼠随机分为对照(Control)组、BLM+PM2.5(Model)组、保肺化纤方(BHF)组、吡非尼酮(pirfenidone,PFD)组、XAV-939组、BHF+PFD组、BHF+XAV-939组。采用一次性气管内雾化BLM法制备IPF大鼠模型,大气PM2.5实时浓缩全身暴露和给予相应药物干预。检测大鼠肺功能,观察肺组织病理和胶原沉积;采用免疫组化技术检测肺组织Ⅰ、Ⅳ型胶原(collagen,COL)、TGF-β1、smad2/3、β-catenin蛋白水平;采用qPCR技术检测肺组织TGF-β1、smad2/3、Wnt1、β-catenin mRNA水平。结果与Control组比较,Model组大鼠肺功能显著降低(P<0.01),肺组织可见大量炎症细胞浸润,肺泡壁断裂、增厚,胶原沉积等肺纤维化特征性病理改变,肺组织胶原容积分数(collagen volume fraction,CVF)、COLⅠ、COLⅣ蛋白及TGF-β1、smad2/3、β-catenin基因与蛋白表达均显著升高(P<0.01);与Model组比较,各治疗组均有效改善大鼠肺组织病理改变,显著降低肺组织CVF及COLⅠ、COLⅣ、TGF-β1、smad2/3、β-catenin蛋白表达水平(P<0.05,P<0.01),同时BHF组、BHF+PFD组、BHF+XAV-939组均能显著提高大鼠肺功能(P<0.05,P<0.01),明显下调肺组织TGF-β1、smad2/3、β-catenin基因表达水平(P<0.01);与PFD组比较,BHF+PFD组大鼠肺组织COLⅠ、TGF-β1蛋白及smad2、β-catenin基因表达均显著降低(P<0.05,P<0.01);与XAV-939组比较,BHF+XAV-939组smad3基因表达显著降低(P<0.01)。结论保肺化纤方可改善BLM/PM2.5诱导的IPF大鼠肺组织病理损伤,减少胶原沉积,提高肺功能,改善肺纤维化,其机制可能与下调TGF-β1/smad2/3、Wnt1/β-catenin通路有关。 展开更多
关键词 特发性肺纤维化 保肺化纤方 胶原沉积 TGF-β1/smad2/3 Wnt1/β-catenin pm2.5
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景观防护林带PM2.5与环境因子的关系研究
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作者 邱苏梅 李立文 +1 位作者 万欣 邢玮 《江苏林业科技》 2024年第3期10-15,共6页
以长江沿岸的典型景观防护林为研究对象,选取榔榆、乌桕、落羽杉和薄壳山核桃4种纯林类型的景观防护林,于2023年监测PM2.5、风速、风向、光照度、空气湿度、空气温度、气压、土壤温度和土壤湿度的季度变化。发现乌桕防护林带PM2.5质量... 以长江沿岸的典型景观防护林为研究对象,选取榔榆、乌桕、落羽杉和薄壳山核桃4种纯林类型的景观防护林,于2023年监测PM2.5、风速、风向、光照度、空气湿度、空气温度、气压、土壤温度和土壤湿度的季度变化。发现乌桕防护林带PM2.5质量浓度变化幅度较大,夏季明显低于冬季,而其他3个防护林带PM2.5质量浓度季节变化幅度不大。通过相关性分析发现PM2.5与多个环境因子有相关性,尤其是乌桕防护林带。为了探究各环境因子对PM2.5的影响,该研究引入随机森林模型,结果表明在长江沿岸的典型景观防护林中空气湿度是影响PM2.5质量浓度的主要环境因子。该研究结果为未来建构科学合理的防护林体系提供了理论依据。 展开更多
关键词 防护林带 pm2.5 环境因子 随机森林模型 长江
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基于MSPA分析绿地形态空间格局对PM2.5的消退作用——以广州市、深圳市为例
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作者 刘迅 廖珊慧 +3 位作者 李智恒 林华威 张驰方 林锦耀 《生态科学》 CSCD 北大核心 2024年第3期186-195,共10页
在土地资源紧张的背景下,优化绿地形态空间格局对提升空气质量具有重要的意义。以往相关研究多采用景观格局指数衡量绿地空间特征,据此研究不同的绿地景观形态对PM2.5的消退作用,但景观格局指数只是反映绿地数量与结构的量化指标,无法... 在土地资源紧张的背景下,优化绿地形态空间格局对提升空气质量具有重要的意义。以往相关研究多采用景观格局指数衡量绿地空间特征,据此研究不同的绿地景观形态对PM2.5的消退作用,但景观格局指数只是反映绿地数量与结构的量化指标,无法落实到具体空间上。为了解决这一不足,以广州市、深圳市为例,基于MSPA探究不同的绿地形态空间格局对PM2.5的消退作用。结果表明:21个研究单元的PM2.5值在时间上变化基本一致,在空间上的高低与附近是否有绿地具有紧密的关系;相关分析中, PM2.5与建设用地面积、孤岛占比呈显著正相关,与核心区占比呈显著负相关;随机森林模型中,分支占比、孤岛占比、道路密度对PM2.5浓度的影响效果较强;市区的PM2.5受核心区占比、孤岛占比的影响较大,而郊区的PM2.5受不同的绿地形态空间格局影响不大。根据分析结果,提出加强保护大型绿色开放空间;整合破碎化绿地,使孤岛绿地形态核心化;构建线状城市绿廊绿道的策略改善PM2.5的污染。基于MSPA揭示了不同绿地形态空间格局对PM2.5的消退作用的机制,所提出的相关策略可以为大气污染防治和城市绿地空间格局的规划管理提供新思路。 展开更多
关键词 MSPA 绿地形态空间格局 pm2.5 广州市 深圳市
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PM2.5对代谢相关脂肪性肝病模型小鼠肝淋巴生成的影响 被引量:1
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作者 丁世彬 李洋 +1 位作者 陈玉萍 蒋金金 《中国实验动物学报》 CAS CSCD 北大核心 2024年第8期985-991,共7页
目的研究大气细颗粒物(particulate matter 2.5,PM2.5)暴露对C57BL/6J小鼠和代谢相关脂肪性肝病模型小鼠肝淋巴生成的影响,为防治PM2.5暴露所致肝损伤提供新靶点。方法将40只雄性C57BL/6J小鼠随机分为正常组,PM2.5组,代谢相关脂肪性肝... 目的研究大气细颗粒物(particulate matter 2.5,PM2.5)暴露对C57BL/6J小鼠和代谢相关脂肪性肝病模型小鼠肝淋巴生成的影响,为防治PM2.5暴露所致肝损伤提供新靶点。方法将40只雄性C57BL/6J小鼠随机分为正常组,PM2.5组,代谢相关脂肪性肝病模型组(MAFLD组)和PM2.5-MAFLD组。MAFLD组和PM2.5-MAFLD组小鼠连续12周给予高脂饲料,其余两组给予普通饲料。从13~16周,PM2.5组和PM2.5-MAFLD组小鼠通过气管滴注法进行PM2.5染毒(每周2次);其余两组小鼠同时通过气管滴注法滴注生理盐水。末次PM2.5染毒结束24 h后将实验动物处死。测定小鼠血清丙氨酸氨基转移酶(alanine aminotransferase,ALT)和天冬氨酸氨基转移酸(aspartate aminotransferase,AST)水平;用免疫荧光染色法评估肝淋巴LYVE1表达水平;测定肝氧化应激指标(4-HNE和T-GSH/GSSG)水平;用蛋白免疫印迹法测定肝淋巴生成标志蛋白(PROX1和LYVE1),淋巴生成调节蛋白VEGF-C和淋巴连接蛋白VE-cadherin的蛋白质表达水平。结果PM2.5染毒显著增加了MAFLD组小鼠血清AST和ALT水平,显著降低了肝组织PROX1、LYVE1和VEGF-C蛋白表达水平,增加肝4-HNE水平和降低了肝T-GSH/GSSG水平(P<0.05)。然而,PM2.5染毒并没有显著影响C57BL/6J小鼠血清AST和ALT水平、肝组织中PROX1、LYVE1、VEGF-C和VE-cadherin的蛋白表达水平及肝的4-HNE和T-GSH/GSSG(P>0.05)。结论PM2.5染毒能显著加重MAFLD小鼠肝的氧化损伤,并且能通过降低肝VEGF-C减少肝淋巴生成。 展开更多
关键词 pm2.5 代谢相关脂肪性肝病 氧化应激 淋巴生成
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Phase precision of Mach–Zehnder interferometer in PM2.5 air pollution
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作者 Duan Xieand Haifeng Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第7期207-213,共7页
This paper theoretically explores the effect of PM2.5 air pollution on the phase precision of a Mach-Zehnder inter- ferometer. With the increasing of PM2.5 concentration, phase precision for inputs of coherent state ... This paper theoretically explores the effect of PM2.5 air pollution on the phase precision of a Mach-Zehnder inter- ferometer. With the increasing of PM2.5 concentration, phase precision for inputs of coherent state & vacuum state and inputs of coherent state & squeezed vacuum state will gradually decrease and be lower than the standard quantum limit. When the value of relative humidity is increasing, the precision of two input cases is decreasing much faster. We also find that the precision for inputs of coherent state & squeezed state is better than that of coherent state & vacuum state when PM2.5 concentration is lower. As PM2.5 concentration increases, the precision for inputs of coherent state & squeezed state decreases faster, and then the two precisions tend to be the same while the concentration is higher. 展开更多
关键词 Mach-Zehnder interferometer pm2.5 phase precision
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融合时空特征的城市多站点PM2.5浓度预测
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作者 黄琨 吴学群 +1 位作者 成飞飞 韩啸 《传感器与微系统》 CSCD 北大核心 2024年第5期149-152,157,共5页
本文提出一种融合时空特征的城市多站点PM2.5预测方法,该方法可以捕捉PM2.5在时间和空间上的相关性,通过将区域多个站点的PM2.5数据转换为一系列静态图像,将其输入到卷积长短期记忆(ConvLSTM)模型中,采用端对端的方式进行训练,预测城市... 本文提出一种融合时空特征的城市多站点PM2.5预测方法,该方法可以捕捉PM2.5在时间和空间上的相关性,通过将区域多个站点的PM2.5数据转换为一系列静态图像,将其输入到卷积长短期记忆(ConvLSTM)模型中,采用端对端的方式进行训练,预测城市未来多个站点多个时段的PM2.5浓度。以北京多个站点的PM2.5数据进行实验验证。结果表明:考虑了时空特征的ConvLSTM方法在短期预测方面优于其他4种时序方法,该方法可为PM2.5预测提供新的思路。 展开更多
关键词 时空特征 卷积长短期记忆 多站点 pm2.5浓度预测
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基于Prophet-LightGBM的PM2.5浓度预测模型
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作者 高洁如 魏霖静 +1 位作者 李玥 王开翔 《软件导刊》 2024年第7期144-152,共9页
近年来,PM2.5污染问题日益突出,对人们的身体健康和环境质量造成了严重影响,建立准确的PM2.5浓度预测模型对于污染防治和空气质量管理具有重要意义。针对PM2.5时间序列的非线性、高噪声、不平稳特征提出一种将Prophet模型和LightGBM模... 近年来,PM2.5污染问题日益突出,对人们的身体健康和环境质量造成了严重影响,建立准确的PM2.5浓度预测模型对于污染防治和空气质量管理具有重要意义。针对PM2.5时间序列的非线性、高噪声、不平稳特征提出一种将Prophet模型和LightGBM模型相结合的组合模型。为了验证模型的有效性,以兰州市PM2.5浓度数据为例,对比分析了Prophet-LightGBM模型和其他4种预测模型及其在不同季节下的预测效果。结果表明,Prophet-LightGBM模型相较于对比模型能够更准确地预测PM2.5浓度的变化趋势,RMSE值达6.557,MAE值达4.543,MAPE值达14.344%,在夏季和秋季的预测准确度和稳定性方面表现出更优异的性能,RMSE值最优时达3.155,MAE值达2.169,MAPE值达9.4%。 展开更多
关键词 pm2.5浓度预测 Prophet模型 LightGBM模型 组合模型
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基于多元回归的延安市PM2.5浓度预测
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作者 王思源 任瑛 +1 位作者 夏必胜 王文发 《信息技术》 2024年第5期15-21,共7页
工业化进程的加快带来的不只是经济的飞速发展,还有以PM2.5为主的污染物浓度的增加,给人类的健康以及环境的治理带来不利影响,合理有效的PM2.5浓度预测对于人类健康和环境治理有着重要意义。文中设计了基于多元回归模型的PM2.5浓度预测... 工业化进程的加快带来的不只是经济的飞速发展,还有以PM2.5为主的污染物浓度的增加,给人类的健康以及环境的治理带来不利影响,合理有效的PM2.5浓度预测对于人类健康和环境治理有着重要意义。文中设计了基于多元回归模型的PM2.5浓度预测模型,分别预测了延安市春季、夏季、秋季和冬季的PM2.5浓度,与极限树回归、Catboost回归和K邻近回归等回归模型的预测结果进行对比。结果表明多元回归模型的误差较小,拟合精度较高,为延安市大气污染的治理提供了可靠的科学依据。 展开更多
关键词 多元回归 pm2.5预测 极限树回归 随机森林
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基于函数型数据模型的PM2.5浓度与温度关系的实证分析
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作者 陈宇庆 凌能祥 《大学数学》 2024年第4期1-6,共6页
考虑在函数型解释变量部分观测的情况下,用函数线性模型刻画与标量响应变量的关系.基于函数型主成分分析(Functional Principal Component Analysis,简称FPCA)实现了对缺失部分样本的重构,并通过实证分析,对一组北京市2010-2014年间统... 考虑在函数型解释变量部分观测的情况下,用函数线性模型刻画与标量响应变量的关系.基于函数型主成分分析(Functional Principal Component Analysis,简称FPCA)实现了对缺失部分样本的重构,并通过实证分析,对一组北京市2010-2014年间统计的包括部分观测PM2.5数值的气象数据,分析了PM2.5作为部分观测函数型解释变量对标量响应变量平均气温的影响,结果表明了该方法具有处理缺失函数数据的现实意义. 展开更多
关键词 函数线性模型 随机缺失 复合分位数回归 pm2.5
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基于深度学习的城市PM2.5浓度时空分布预测及不确定性评估
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作者 刘慧敏 张陈为 +2 位作者 谌恺祺 邓敏 彭翀 《测绘学报》 EI CSCD 北大核心 2024年第4期750-760,共11页
城市PM2.5浓度的时空分布预测旨在基于有限观测样本实现研究区域内PM2.5分布的全范围感知。理想的预测模型需同时保证结果的高精度与高可靠性。然而,现有研究大多以提升精度为唯一目的,忽视了由于数据质量与模型结构的各异所导致预测结... 城市PM2.5浓度的时空分布预测旨在基于有限观测样本实现研究区域内PM2.5分布的全范围感知。理想的预测模型需同时保证结果的高精度与高可靠性。然而,现有研究大多以提升精度为唯一目的,忽视了由于数据质量与模型结构的各异所导致预测结果的不确定性,这极大限制了高精度预测结果的可靠性与可用潜力,从而难以有效辅助空气污染治理等实际应用。为此,本文提出一种耦合不确定性评估的PM2.5浓度时空分布预测模型。通过构建以图卷积和循环网络为主的预测模块,实现PM2.5浓度的高精度预测;同时,基于对抗学习策略与变分自编码思想构建不确定性量化模块,同步揭示预测结果的不确定性水平。深圳市实际数据实证表明,本文方法能有效兼顾PM2.5浓度预测结果的精度与可靠性,能为包括监测站点布局选址在内的环境治理工作提供科学决策支持。 展开更多
关键词 pm2.5 深度学习 不确定性 地理预测
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二甲双胍通过抑制铁死亡改善PM2.5导致的胎盘滋养细胞功能损伤
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作者 李淑贤 于淑平 +3 位作者 穆亚铭 王凯 刘玉 张美华 《南方医科大学学报》 CAS CSCD 北大核心 2024年第3期437-446,共10页
目的探究PM2.5损伤胎盘滋养细胞导致不良妊娠结局的作用机制及二甲双胍的挽救作用。方法将16只孕鼠随机分为空白组(n=8),PM2.5染毒组(n=8),两组分别在妊娠1.5、7.5、12.5 d通过气管滴注PBS和PM2.5悬浮液。观察PM2.5对孕鼠妊娠结局的影响... 目的探究PM2.5损伤胎盘滋养细胞导致不良妊娠结局的作用机制及二甲双胍的挽救作用。方法将16只孕鼠随机分为空白组(n=8),PM2.5染毒组(n=8),两组分别在妊娠1.5、7.5、12.5 d通过气管滴注PBS和PM2.5悬浮液。观察PM2.5对孕鼠妊娠结局的影响,并通过HE染色观察小鼠胎盘病理结构,检测胎盘组织铁死亡相关指标。体外构建PM2.5暴露的人类胎盘滋养细胞系HTR8/SVneo细胞染毒模型,利用CCK8实验检测细胞活性;利用EDU染色检测细胞增殖能力;利用划痕实验检测细胞迁移能力;利用Transwell实验检测细胞侵袭能力;利用成管实验检测细胞管生成能力;通过ELISA和Western blotting等方法分析铁死亡相关指标的表达。结果体内实验显示PM2.5导致胎鼠的质量下降(P<0.001)、数目减少(P<0.01)、死亡率增加(P<0.001),同时胎盘质量也显著减少(P<0.001),HE染色结果显示胎盘的结果受损;组织免疫荧光、ELISA及Western blotting结果表明PM2.5导致胎盘铁死亡的发生。体外实验显示PM2.5通过导致胎盘滋养细胞铁死亡抑制细胞增殖、迁移、侵袭、成管等生物学活性;二甲双胍可显著逆转PM2.5导致的滋养细胞铁死亡,包括细胞内GSH浓度和SOD活性增高(P<0.01)、MDA浓度降低和Fe离子含量降低(P<0.001)、GPX4蛋白和SLC7A11蛋白表达增高(P<0.05)等,同时二甲双胍显著改善PM2.5导致的细胞增殖、迁移、侵袭、成管等生物学功能损伤。结论PM2.5导致孕鼠不良妊娠结局及胎盘滋养细胞铁死亡和功能障碍,应用二甲双胍可有效改善细胞损伤。 展开更多
关键词 pm2.5 滋养细胞 铁死亡 二甲双胍
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Distribution and Formation Causes of PM_(2.5) and O_(3) Double High Pollution Events in China during 2013–20
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作者 Zhixuan TONG Yingying YAN +6 位作者 Shaofei KONG Jintai LIN Nan CHEN Bo ZHU Jing MA Tianliang ZHAO Shihua QI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1235-1250,I0004-I0021,共34页
Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribu... Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribution of DHP events in China during 2013–20 is analyzed.The synoptic types affecting DHP events are identified with the Lamb–Jenkinson circulation classification method.The meteorological and chemical causes of DHP events controlled by the main synoptic types are further investigated.Results show that DHP events(1655 in total for China during 2013–20)mainly occur over the North China Plain,Yangtze River Delta,Pearl River Delta,Sichuan Basin,and Central China.The occurrence frequency increases by 5.1%during 2013–15,and then decreases by 56.1%during 2015–20.The main circulation types of DHP events are“cyclone”and“anticyclone”,accounting for over 40%of all DHP events over five main polluted regions in China,followed by southerly or easterly flat airflow types,like“southeast”,“southwest”,and“east”.Compared with non-DHP events,DHP events are characterized by static or weak wind,high temperature(20.9℃ versus 23.1℃)and low humidity(70.0%versus 64.9%).The diurnal cycles of meteorological conditions cause PM_(2.5)(0300–1200 LST,Local Standard Time=UTC+8 hours)and O_(3)(1500–2100 LST)to exceed the national standards at different periods of the DHP day.Three pollutant conversion indices further indicate the rapid secondary conversions during DHP events,and thus the concentrations of NO_(2),SO_(2) and volatile organic compounds decrease by 13.1%,4.7%and 4.4%,respectively.The results of this study can be informative for future decisions on the management of DHP events. 展开更多
关键词 double high pollution events PM_(2.5) OZONE spatiotemporal distribution meteorological causes chemical composition characteristics
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