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Potential of secondary aerosol formation from Chinese gasoline engine exhaust

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Journal of Environmental Sciences 2018年第4期30卷 348-357页

作者： Zhuofei Du Min Hu Jianfei Peng Song Guo Rong zheng Jing zheng Dongjie Shang Yanhong Qin He Niu Mengren Li yudong Yang Sihua Lu Yusheng Wu Min Shao Shijin Shuai State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University State key Laboratory of Automotive Safety and Energy Department of Automotive Engineering Tsinghua University

Light-duty gasoline vehicles have drawn public attention in China due to their significant primary emissions of particulate matter and volatile organic compounds（VOCs）. However,little information on secondary aerosol formation from exhaust for Chinese vehicles and fuel conditions is available. In this study, chamber experiments were conducted to quantify the potential of secondary aerosol formation from the exhaust of a port fuel injection gasoline engine. The engine and fuel used are common in the Chinese market, and the fuel satisfies the China V gasoline fuel standard. Substantial secondary aerosol formation was observed during a 4–5 hr simulation, which was estimated to represent more than 10 days of equivalent atmospheric photo-oxidation in Beijing. As a consequence, the extreme case secondary organic aerosol（SOA） production was 426 ± 85 mg/kg-fuel, with high levels of precursors and OH exposure. The low hygroscopicity of the aerosols formed inside the chamber suggests that SOA was the dominant chemical composition. Fourteen percent of SOA measured in the chamber experiments could be explained through the oxidation of speciated single-ring aromatics. Unspeciated precursors, such as intermediate-volatility organic compounds and semi-volatile organic compounds, might be significant for SOA formation from gasoline VOCs. We concluded that reductions of emissions of aerosol precursor gases from vehicles are essential to mediate pollution in China.

关键词： Port fuel injection Gasoline engine exhaust Secondary aerosol formation Chamber simulation Secondary organic aerosol

中国80岁及以上老年人睡眠时长及体育锻炼与血脂异常的关联

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中华流行病学杂志 2024年第1期45卷 48-55页

作者：吴兵李阳徐岚静章正周锦辉魏源陈晨王君吴昌恣李峥胡子雨龙范晔吴玉栋胡雪华李可馨李方玙罗宇菲刘迎春吕跃斌施小明南京医科大学公共卫生学院全球健康中心南京211166 中国疾病预防控制中心环境与人群健康重点实验室/环境与健康相关产品安全所北京100021 浙江大学公共卫生学院杭州310058 吉林大学公共卫生学院长春130012

目的探讨中国≥80岁老年人(高龄老人)睡眠时长、体育锻炼及其交互作用对血脂异常发生风险的影响。方法调查对象为老年健康生物标志物队列研究项目四轮调查(2008-2009年、2011-2012年、2014年和2017-2018年)中的高龄老人。收集人口学特... 详细信息

目的探讨中国≥80岁老年人(高龄老人)睡眠时长、体育锻炼及其交互作用对血脂异常发生风险的影响。方法调查对象为老年健康生物标志物队列研究项目四轮调查(2008-2009年、2011-2012年、2014年和2017-2018年)中的高龄老人。收集人口学特征、生活方式、体格检查等资料,收集空腹静脉血进行血脂检测。采用竞争风险模型探索睡眠时长及体育锻炼与血脂异常发生风险之间的因果关联。应用限制性立方样条(RCS)函数分析睡眠时长与血脂异常发生风险的剂量-反应关系,采用相加及相乘交互作用模型探索睡眠时长和体育锻炼对血脂异常发生风险的交互作用。结果1809名研究对象的年龄为(93.1±7.7)岁,女性占65.1%。基线调查睡眠时长为(8.0±2.5)h/d,睡眠时长9 h/d者占27.2%。累积随访6150.6人年(人均随访3.4年),血脂异常新发病例304名,发病密度为4942.6/10万人年。竞争风险模型结果表明,与睡眠时长为7~h/d者相比,>9 h/d者血脂异常发生风险增加22%(HR=1.22,95%CI:1.07~1.39);与不进行体育锻炼的高龄老人相比,进行体育锻炼的高龄老人血脂异常发生风险降低33%(HR=0.67,95%CI:0.57~0.78)。RCS函数分析显示,在高龄老人中睡眠时长与血脂异常发生风险具有正向线性的剂量-反应关系。交互作用分析显示,体育锻炼与睡眠时长对血脂异常发生风险存在拮抗作用。结论体育锻炼可能会改善睡眠时长过长对高龄老人血脂的不良影响。

关键词：高龄老人睡眠时长体育锻炼血脂异常队列研究

Impact of switching frequencies on the TID response of SiC power MOSFETs

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Journal of Semiconductors 2021年第8期42卷 73-76页

作者： Sheng Yang Xiaowen Liang Jiangwei Cui Qiwen zheng Jing Sun Mohan Liu Dang Zhang Haonan Feng Xuefeng Yu Chuanfeng Xiang yudong Li Qi Guo Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics and ChemistryChinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Electronic Information Material and Device Urumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Different switching frequencies are required when SiC metal-oxide-semiconductor field-effect transistors(MOSFETs)are switching in a space *** this study,the total ionizing dose(TID)responses of SiC power MOSFETs are investigated under different switching frequencies from 1 kHz to 10 MHz.A significant shift was observed in the threshold voltage as the frequency increased,which resulted in premature failure of the drain-source breakdown voltage and drain-source leakage *** degradation is attributed to the high activation and low recovery rates of traps at high *** results of this study suggest that a targeted TID irradiation test evaluation method can be developed according to the actual switching frequency of SiC power MOSFETs.

关键词： SiC power MOSFET switching frequency oxide trap total ionizing dose transistor semiconductor theory

基于原位LAMP技术的牡蛎疱疹病毒(OsHV-1)易感宿主调查

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渔业科学进展 2023年第2期44卷 174-185页

作者：张翔谷莉郑玉东李晨白昌明辛鲁生王崇明刘金兰天津农学院水产学院、天津市水产生态及养殖重点实验室天津300384 中国水产科学研究院黄海水产研究所、青岛海洋科学与技术试点国家实验室海洋渔业科学与食物产出过程功能实验室农业农村部海水养殖病害防治重点实验室、青岛市海水养殖流行病学与生物安保重点实验室山东青岛266071 中国海洋大学水产动物病害与免疫学实验室山东青岛266003

牡蛎疱疹病毒(Ostreidherpesvirus1,Os HV-1)给世界双壳贝类养殖业造成了严重的经济损失。10余种双壳贝类陆续被认定为易感宿主,仍有其他几种贝类仅有PCR核酸阳性数据,因确诊证据不足导致其易感性未得到充分评估。原位环介导等温核酸扩... 详细信息

牡蛎疱疹病毒(Ostreidherpesvirus1,Os HV-1)给世界双壳贝类养殖业造成了严重的经济损失。10余种双壳贝类陆续被认定为易感宿主,仍有其他几种贝类仅有PCR核酸阳性数据,因确诊证据不足导致其易感性未得到充分评估。原位环介导等温核酸扩增(LAMP)检测技术相对传统原位杂交技术具有灵敏度高、方便快捷、可作为病原微生物感染证据的优点。为了在Os HV-1流行病学调查过程中实现病毒感染的快速检测和确诊,根据已报道的Os HV-1特异性LAMP检测引物,设计内引物,优化反应条件,建立了Os HV-1的原位LAMP检测方法。基于该方法对2019年以来采集的长牡蛎(Crassostreagigas)、福建牡蛎(Crassostrea angulata)、栉孔扇贝(Chlamysfarreri)、虾夷扇贝(Mizuhopecten yessoensis)、毛蚶(Scapharca subcrenata)和菲律宾蛤仔(Ruditapes philippinarum)样本进行检测。结果显示,毛蚶样本的Os HV-1原位LAMP检测结果呈阳性;其他几种贝类部分样本的实时定量PCR (qPCR)检测呈阳性,但原位LAMP检测呈阴性。对毛蚶样本的原位LAMP检测结果分析发现,病毒杂交信号主要分布在外套膜和肝胰腺等器官的结缔组织,推测感染的细胞为成纤维细胞和血淋巴细胞;在闭壳肌和斧足肌肉组织的肌细胞细胞核中也发现较多杂交信号。鳃丝内和周边偶现阳性信号,推测来自渗出的血淋巴细胞。基于原位LAMP技术的Os HV-1检测结果显示,毛蚶是Os HV-1的一种易感宿主,毛蚶结缔组织、肌肉组织和血淋巴细胞对该病毒有强亲嗜性。

关键词：牡蛎疱疹病毒原位LAMP 易感性流行病学调查

Using GIS Spatial Distribution to Predict Soil Organic Carbon in Subtropical China

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Pedosphere 2004年第4期14卷 425-431页

作者： CHENGXian-Fu SHIXue-zheng yudong-Sheng PANXian-Zhang WANGHong-Jie SUNWei-Xia StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）. Departmentofgeography AnhuiNormalUniversityWuhu241000（China）

Spatial distribution of organic carbon in soils is difficult to estimatebecause of inherent spatial variability and insufficient data. A soil-landscape model for a region,based on 151 samples for parent material and topographic factors, was established using a GISspatial analysis technique and a digital elevation model (DEM) to reveal spatial distributioncharacteristics of soil organic carbon (SOC). Correlations between organic carbon and topographicfactors were analyzed and a regression model was established to predict SOC content. Results forsurface soils (0-20 cm) showed that the average SOC content was 12.8 g kg^(-1), with the SOC contentbetween 6 and 12 g kg^(-1) occupying the largest area and SOC over 24 g kg^(-1) the smallest. Also,soils derived from phyllite were the highest in the SOC content and area, while soils developed onpurple shale the lowest. Although parent material, elevation, and slope exposure were allsignificant topographic variables (P < 0.01), slope exposure had the highest correlation to SOCcontent (r = 0.66). Using a multiple regression model (R^2 = 0.611) and DEM (with a 30 m X 30 mgrid), spatial distribution of SOC could be forecasted.

关键词： digital elevation model parent material regression model soil organiccarbon topography

Ancient genomes reveal the genetic inheritance and recent introgression in Chinese indigenous pigs

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Science China(Life Sciences) 2022年第4期65卷 842-845页

作者： Jia Wen Zhuqing zheng Mian Gong Dong Li Songmei Hu yudong Cai Yongdi Wang Hojjat Asadollahpour Nanaei Naifan Zhang Taiyong Yu Dawei Cai Yu Jiang Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYanglingXianyang712100China Research Center for Chinese Frontier Archaeology Jilin UniversityChangchun130012China Human Phenome Institute Fudan UniversityShanghai201203China Key Laboratory of Agricultural Animal Genetics Breeding and ReproductionMinistry of Education&College of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan430070China Shaanxi Academy of Archaeology Xi’an710054China

Dear Editor,As one of the oldest domesticated livestock, pigs were independently domesticated in the Near East and East Asia,approximately 10,000 years ago (Larson et al., 2010).

关键词： domestica Ancient pigs

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基于响应曲面法的双丝三弧堆焊工艺参数优化

焊接 2024年第5期 30-36页

作者：马振闫玉东史畅吴锦华王碧霞郑建明张二林浙江万丰科技开发股份有限公司浙江绍兴312400 东北大学沈阳110167 佳木斯大学黑龙江佳木斯150007

为了优化双丝三弧焊堆焊工艺参数和预测堆焊稀释率和焊接电流,基于响应曲面法建立了双丝间电流(M弧电流)、主弧电压等焊接工艺参数与稀释率和焊接电流的数学模型。利用Design-Expert软件对稀释率和焊接电流响应进行方差分析、模型显著... 详细信息

为了优化双丝三弧焊堆焊工艺参数和预测堆焊稀释率和焊接电流,基于响应曲面法建立了双丝间电流(M弧电流)、主弧电压等焊接工艺参数与稀释率和焊接电流的数学模型。利用Design-Expert软件对稀释率和焊接电流响应进行方差分析、模型显著性检验及模型信噪分析,研究了堆焊工艺参数对稀释率和焊接电流的影响规律,并对堆焊工艺进行了优化设计,以及结果验证。结果表明,M弧电流对焊接电流和稀释率的影响比较显著;增加M弧电流,焊接电流减小,基材熔化量变小,稀释率越小;减小熔化母材过多的进入堆焊层,保证金属粉芯焊丝的有效成分,有利于堆焊合金材料组织和耐磨性的控制。经过优化设计获得最佳堆焊工艺参数主弧电压为35 V,M弧电流为260 A,送丝速度为10 m/min,频率为70 Hz,占空比50%。

关键词：双丝三弧焊堆焊稀释率响应曲面法

Functional Rehabilitation of the "Soil Reservoir"in Degraded Soils to Control Floods in the Yangtze River Watershed

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Pedosphere 2004年第1期14卷 1-8页

作者： SHIXue-zheng LIANGYin yudong-Sheng PANXian-Zhang[ E.D.WARNER WANGHong-Jie InstituteofSoilScience ChineseAcademyofSciencesNanjing210008（China） EnvironmentalResourcesResearchInstitute ThePennsylvaniaStateUniversityUniversityPark（USA）

The reasons for the Yangtze River flood calamity in 1998 are briefly introduced. The authors believe that using a 'soil reservoir' concept is an important means to help control flooding of the Yangtze River.A 'soil reservoir' has a large potential storage capacity and its water can be rapidly 'discharged' into the underground water in a timely fashion. The eroded, infertile soils of the Yangtze River Watershed are currently an obstacle to efficient operation of the 'soil reservoir'. The storage capacity of this 'soil reservoir'has been severely hampered due to intensive soil erosion and the formation of soil crusts. Therefore, possible measures to control floods in the Yangtze River Watershed include: rehabilitating the vegetation to preserve soil and water on the eroded infertile soils, enhancing infiltration of the different soil types, and utilizing the large 'soil reservoir' of the upper reaches of the Yangtze River.

关键词： flood calamity soil erosion 'soil reservoir' the yangtze river watershed

EZH2 identifies the precursors of human natural killer cells with trained immunity

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Cancer Biology & Medicine 2021年第4期18卷 1021-1039页

作者： Chen Zhang Jie Yin Jian zheng Jun Xiao Jiajian Hu yudong Su Kaichen Zhou Yingchi Zhang Xuzhen Zhang Hong Zhang Qian Sun Yang Wang Wenwen Yu Feng Wei Qiang Zhao Long Li Xiubao Ren Department of Immunology and Biotherapy Key Laboratory of Cancer Immunology and BiotherapyTianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerTianjin 300060China Department of Immunology Key Laboratory of Immune Microenvironment and Disease of the Ministry of EducationTianjin Medical UniversityTianjin 300070China Department of Pediatric Cancer Tianjin Medical University Cancer Institute and HospitalTianjin 300060China State Key Laboratory of Experimental Hematology and Division of Pediatric Blood Diseases Center Institute of Hematology and Blood Diseases HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300000China Center for Stem Cell Medicine Chinese Academy of Medical SciencesBeijing 100730China Research Center of Basic Medicine Science Tianjin Medical UniversityTianjin 300070China

Objective:Trained immunity of natural killer(NK)cells has shown great potential in the treatment of cancers by eliciting enhanced effector responses to restimulation by cytokines or cancer cells for long time periods after ***,the human NK cells responsible for the generation and maintenance of trained immunity are largely *** hypothesized that heterogeneous human NK cells would respond differentially to stimulation with a combination of IL-12,IL-15,and IL-18,and that an NK cell subset might exist that is mainly responsible for the induction of trained *** the basis of our hypothesis,we aimed to identify the subset from which cytokine-trained human NK cells originate and to explore possible regulatory targets for drug ***:Flow cytometry assays were performed to analyze the functions of cytokine-trained NK cells and examine cell division and protein expression in NK cell ***-cell RNA sequencing(scRNA-seq)plus TotalSeq™technology was used to track the heterogeneity of NK cells during the induction of trained ***:Traditional developmental markers for peripheral NK cells were unable to identify the precursors of human NK cells with trained ***,we used scRNA-seq plus TotalSeq™technology to track the heterogeneity of NK cells during the induction of trained immunity and identified a unique cluster of CD57−NKG2A+EZH2+IFNG+MKI67+IL12R+IL15R+IL18R+NK *** and pseudotime trajectory analyses suggested that this cluster of NK cells contained the precursor of trained NK *** then used flow cytometry to further investigate the role of EZH2 in trained NK precursors and found that CD57−NKG2A+EZH2+NK cells had faster cell cycles and an enhanced trained phenotype,and EZH2 inhibition significantly impaired the induction of trained immunity in NK *** results suggested that EZH2 is a unique epigenetic marker of precursors of human NK cells with trained ***:Ou

关键词： Natural killer cells trained immunity precursor EZH2 cell cycle