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Spatiotemporal variations of ambient air pollutants and meteorological influences over typical urban agglomerations in China during the COVID-19 lockdown

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Journal of Environmental Sciences 2021年第8期33卷 26-38页

作者： linping fan Shuang Fu Xin Wang Qingyan Fu Haohao Jia Hao Xu Guimei Qin Xue Hu Jinping Cheng School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China China National Environmental Monitoring Center Beijing 100012China Shanghai Environmental Monitor Center Shanghai 200235China

To investigate the air quality change during the COVID-19 pandemic,we analyzed spatiotemporal variations of six criteria pollutants in nine typical urban agglomerations in China using ground-based data and examined meteorological influences through correlation analysis and backward trajectory analysis under different *** of PM2.5,PM10,NO2,SO2 and CO in urban agglomerations respectively decreased by 18%–45%(30%–62%),17%–53%(22%–39%),47%-64%(14%–41%),9%–34%(0%–53%)and 16%-52%(23%–56%)during Lockdown(Post-lockdown)period relative to Pre-lockdown ***2.5 pollution events occurred during Lockdown in Beijing-Tianjin-Hebe(BTH)and Middle and South Liaoning(MSL),and daily O3 concentration rose to gradeⅡstandard in Post-lockdown *** from the nationwide slump of NO2 during Lockdown period,a rebound(~40%)in Post-lockdown period was observed in Cheng-Yu(CY),Yangtze River Middle-Reach(YRMR),Yangtze River Delta(YRD)and Pearl River Delta(PRD).With slightly higher wind speed compared with 2019,the reduction of PM2.5(51%–62%)in Post-lockdown period is more than2019(15%–46%)in HC(Harbin-Changchun),MSL,BTH,CP(Central Plain)and SP(ShandongPeninsula),suggesting lockdown measures are effective to PM2.5 *** O3 concentrations generally increased during the lockdown,its increment rate declined compared with 2019 under similar sunlight duration and ***,unlike HC,MSL and BTH,which suffered from additional(>30%)air masses from surrounding areas after the lockdown,the polluted air masses reaching YRD and PRD mostly originated from the long-distance transport,highlighting the importance of joint regional governance.

关键词： COVID-19 Air pollutants Spatial and temporal variations Urban agglomeration Meteorological condition China

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高毒力肺炎克雷伯菌hfq基因缺失株的构建及其生物学特性分析

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中华微生物学和免疫学杂志 2022年第10期42卷 769-776页

作者：魏丹丹熊晓顺陈思黄旗森黄珊珊范琳萍刘洋南昌大学第一附属医院检验科南昌330006 南昌大学第二附属医院检验科南昌330006

目的构建高毒力肺炎克雷伯菌NTHU-K2044菌株hfq基因缺失株(△hfq),并通过表型试验分析hfq基因对高毒力肺炎克雷伯菌生长特性、环境适应能力和毒力等生物学特性的影响。方法利用同源重组技术对NTUH-K2044菌株进行hfq基因敲除;通过表型试... 详细信息

目的构建高毒力肺炎克雷伯菌NTHU-K2044菌株hfq基因缺失株(△hfq),并通过表型试验分析hfq基因对高毒力肺炎克雷伯菌生长特性、环境适应能力和毒力等生物学特性的影响。方法利用同源重组技术对NTUH-K2044菌株进行hfq基因敲除;通过表型试验,比较高毒力肺炎克雷伯菌野生株和△hfq突变株在细菌生长速度、抗环境胁迫能力、生物膜形成、荚膜形成中性粒细胞杀菌活性和大蜡螟幼虫感染致死率等方面的差异性。结果成功构建高毒力肺炎克雷伯菌NTUH-K2044△hfq缺失株,表型试验表明△hfq缺失株的生长速度显著减慢,菌落变小和超黏性下降;在pH9、pH5.5、0.7 mmol/L SDS、5%NaCl、0.1%H2O2环境和50℃高温等环境胁迫条件下,△hfq缺失株生长受到显著抑制;在毒力方面,△hfq缺失株生物膜形成能力下降,荚膜形成能力下降且荚膜合成基因magA和rmpA表达量明显下降,中性粒细胞杀菌试验存活率下降,大蜡螟幼虫致死能力显著降低。结论Hfq蛋白作为RNA伴侣分子能够参与转录后调控进而对高毒力肺炎克雷伯菌生理、环境适应性及毒力致病性具有重要的调控作用。这为寻找治疗和控制高毒力高耐药肺炎克雷伯菌新靶标提供了基础。

关键词：高毒力肺炎克雷伯菌 hfq基因同源重组环境适应

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长三角地区2000—2019年黑碳排放核算及其不确定性

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地球环境学报 2023年第1期14卷 86-97,109页

作者：李舒惠曹闪闪杨依程丹阳樊林平刘敏华东师范大学生态与环境科学学院、上海市城市化生态过程与生态恢复重点实验室上海200241 华东师范大学崇明生态研究院上海202162

基于国家能源活动统计资料,使用排放因子法建立了长三角地区2000—2019年黑碳排放清单,并利用Monte Carlo方法量化排放因子对黑碳排放核算的影响及不确定性。研究结果表明:(1)近20 a长三角地区总黑碳排放量由10.72×10^(7)kg(2000年)增... 详细信息

基于国家能源活动统计资料,使用排放因子法建立了长三角地区2000—2019年黑碳排放清单,并利用Monte Carlo方法量化排放因子对黑碳排放核算的影响及不确定性。研究结果表明:(1)近20 a长三角地区总黑碳排放量由10.72×10^(7)kg(2000年)增加至12.54×10^(7)kg(2019年),增长了16.98%;黑碳排放源结构发生显著变化,2000年居民生活是长三角地区最主要的黑碳排放源(占42.2%);自2006年开始工业逐渐成为研究区最主要的黑碳排放源,2019年工业排放占长三角地区黑碳排放总量的63.2%。(2)长三角地区黑碳排放存在明显的空间分异。总体而言,江苏省黑碳排放总量和人均黑碳排放强度居长三角地区首位,安徽省单位GDP黑碳排放最高,上海市单位面积黑碳排放强度最高,而浙江省人均和单位面积黑碳排放强度最低。(3)考虑黑碳排放核算过程中排放因子的取值差异,2019年长三角地区黑碳排放总量为7.13×10^(7)—14.49×10^(7)kg(95%置信区间),相对不确定性为-33.50%—35.11%。工业排放因子是长三角黑碳排放核算不确定性的主要贡献者。

关键词：黑碳排放清单不确定性长三角地区

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Effects of initial particle gradation and rock content on crushing behaviors of weathered phyllite fills——A case of eastern Ankang section of Shiyan—Tianshui highway,China

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第2期12卷 269-278页

作者： Feifei Liu Xuesong Mao Yushuo fan linping Wu Wei Victor Liu School of Highway Chang'an UniversityXi'anChina Shijiazhuang Transportation Survey and Design Institute ShijiazhuangChina Department of Civil and Environmental Engineering University of AlbertaEdmontonCanada

The objective of this paper is to investigate the effects of initial particle gradation and rock content on the crushing behavior(*** size before and after crushing) of weathered phyllite *** tests were conducted on weathered phyllite fills with rock contents of 35%,45%,55%,65% and 75%(by weight).First,the particle size distributions(PSDs) were observed before and after compaction,and then the particle breakage of weathered phyllite fills was analyzed by fractal *** fractal dimension was proposed to evaluate the effects of initial rock content and initial gradation on the particle *** was found that the fractal dimension method can well characterize the crushing behaviors of the weathered phyllite *** finer the fills were,the more they were *** is,after the first compaction,the relative fractal dimension of the weathered phyllite fills increased as the rock content increased,reaching the values of 0.013,0.016,0.024,0.037 and 0.08,*** the second compaction,these relative fractal dimension values,dominated by the initial particle gradation,became 0.059,0.072,0.052,0.095 and 0.118,*** conclusion,the weathered phyllite fills with 55% rock content exhibited the least breakage and were most suitable for filling the *** in this paper will provide significant guidance for the construction of weathered phyllite filling subgrade in future projects.

关键词： Weathered phyllite fills Crushing behavior Compaction test Fractal dimension Relative fractal dimension

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Effects of electrostimulation and administration of succinylcholine on the expression of Fos protein in mesencephalic periaqueductal gray matter of rats after simulated weightlessness

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Neural Regeneration Research 2006年第1期1卷 22-25页

作者： Yongjin Zhu Sudi Wu Xiaoli fan Xinai Song linping Xu Department of Physiology Medical School Xi＇an Jiaotong University Xi＇an 710061 Shaanxi Province China Key Laboratory of Environment and Genes Related to Diseases Xi＇an Jiaotong University Min istry of Education Xi＇an 710061. Shaanxi Province China

BACKGROUND： Expression of Fos in neurons of periaqueductal gray （PAG） is used to reflect the excitability. However, changes of expression of Fos in neurons of PAG are caused by injured electrostimulation after simulated weightlessness, and the relationship between pretreatment and injection of succinylcholine has not been determined yet. OBJECTIVE ： To investigate the changes of expression of Fos in PAG induced by injured electrostimulation pretreatment and injection of succinylcholine at 2 weeks after simulated weightlessness.DESIGN： Observational and controlled animal study.SETTING： Department of Physiology, Medical School, Xi＇an Jiaotong University; Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education. MATERIALS： A total of 24 adult female SD rats, of clean grade and weighing 180-220 g, were selected in this study. METHODS： The experiment was completed in the Experimental Animal Center of Xi＇an Jiaotong University.① All rats were randomly divided into 2 groups according to body mass： simulated weightlessness group and control group with 12 in each group. And then, each group was also divided into 3 subgroups： electrostimulation group, succinylcholine-pretreatment group and succinylcholine-injection group with 4 in each subgroup. ②The model of weightlessness was simulated by tail-suspended female rats, which were described and modified by Cheng Jie. Rats in normal control group were given the same interventions as simulated weightlessness group except for tail-suspended. ③ Experimental method： The rats in electrostimulation group were given nociceptive stimulus by a pair of subcutaneous electrodes inserted into 1 and 5 claw of left hindlimb. The stimulus （current： 10 mA; duration： 1 ms; interval： 1 s） lasted for 30 minutes. The rats in succinylcholine-pretreatment group received stimulus after intravenous administration of succinylcholine, rats in succinylcholine-injection group were not given stimulus, just received succiny

关键词： Fos Effects of electrostimulation and administration of succinylcholine on the expression of Fos protein in mesencephalic periaqueductal gray matter of rats after simulated weightlessness

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基于vSphere技术的农业科研云平台研究和构建

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山西农业科学 2017年第11期45卷 1863-1866,1882页

作者：杨方陈晓冬杨蕊崔玉祥曹宇宾赵慧芳韩晋潘大丰张婧文范林平山西省农业科学院农业科技信息研究所山西太原030031 山西省农业广播电视学校实践培训基地山西太原030002

云计算技术已成为当前发展现代农业的重要技术支撑,农业科研基础领域对于数据计算分析性能的需求日渐增长。从理论、技术和实践3个维度出发,详细论述了构建农业科研云平台的过程,包括云计算理论、vSphere技术、基础设施、规划和实施细节... 详细信息

云计算技术已成为当前发展现代农业的重要技术支撑,农业科研基础领域对于数据计算分析性能的需求日渐增长。从理论、技术和实践3个维度出发,详细论述了构建农业科研云平台的过程,包括云计算理论、vSphere技术、基础设施、规划和实施细节等,列举了农业科研云平台具体应用场景,最后探讨了预期开展的云服务。

关键词： vSphere 云平台 IaaS 分布式交换机虚拟机生物信息学现代农业

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Real-time observation of vortex mode switching in a narrow-linewidth mode-locked fiber laser

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Photonics Research 2020年第7期8卷 1203-1212页

作者： Jiafeng Lu fan Shi Linghao Meng Longkun Zhang linping Teng Zhengqian Luo Peiguang Yan Fufei Pang Xianglong Zeng Key Laboratory of Specialty Fiber Optics and Optical Access Networks Joint International Research Laboratory of Specialty Fiber Optics and Advanced CommunicationShanghai UniversityShanghai 200444China Department of Electronic Engineering School of Information Science and EngineeringXiamen UniversityXiamen 361005China Shenzhen Key Laboratory of Laser Engineering Shenzhen UniversityShenzhen 518060China

Temporal and spatial resonant modes are always possessed in physical systems with energy *** ultrafast fiber lasers,enormous progress has been made toward controlling the interactions of many longitudinal modes,which results in temporally mode-locked ***,optical vortex beams have been extensively investigated due to their quantized orbital angular momentum,spatially donut-like intensity,and spiral phase *** this paper,we have demonstrated the first to our knowledge observation of optical vortex mode switching and their corresponding pulse evolution dynamics in a narrow-linewidth mode-locked fiber *** spatial mode switching is achieved by incorporating a dual-resonant acousto-optic mode converter in the vortex mode-locked fiber *** vortex mode-switching dynamics have four stages,including quiet-down,relaxation oscillation,quasi mode-locking,and energy recovery prior to the stable mode-locking of another vortex *** evolution dynamics of the wavelength shifting during the switching process are observed via the time-stretch dispersion Fourier transform *** spatial mode competition through optical nonlinearity induces energy fluctuation on the time scale of ultrashort pulses,which plays an essential role in the mode-switching dynamic *** results have great implications in the study of spatial mode-locking mechanisms and ultrashort laser applications.

关键词： fiber mode narrow

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Factors associated with dysglycemia and its post-surgical resolution in patients with pheochromocytomas

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Science China(Life Sciences) 2023年第2期66卷 411-414页

作者： Lin Zhao Xu Meng Qiongyu Zhang Yi Zhou Ting Zhang Tao Tian Hua fan Huadong Zhu Yecheng Liu fang Luo linping Wang Weixian Yang Xianliang Zhou Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseaseChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100037China Emergency Department State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Family Medicine&Division of General Internal Medicine Department of MedicineState Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Urology State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Dear Editor,Pheochromocytomas are rare neuroendocrine tumors originating from chromaffin cells in the adrenal medulla(Neumann et al., 2019). A number of case reports and small cohorts have reported the association between dysglycemia and pheochromocytomas(Elenkova et al., 2020;Khatiwada et al., 2020;Krumeich et al., 2021). However, there are few large sample studies reporting the outcomes of dysglycemia in patients with pheochromocytomas after resection.

关键词： patients cytoma

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温拌沥青混合料马歇尔击实和旋转压实密实曲线的比较分析

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公路工程 2015年第1期40卷 29-32,47页

作者：李林萍张帆新疆大学建筑工程学院新疆乌鲁木齐830047

根据由不同马歇尔击实次数成型得到的密实度比随击实次数变化所形成的密实曲线,与旋转压实一次成型得到的密实曲线作比较,以此分析温拌沥青混合料和热拌沥青混合料的压实特性。由马歇尔击实和旋转压实密实曲线、密实度斜率和密实度能量... 详细信息

根据由不同马歇尔击实次数成型得到的密实度比随击实次数变化所形成的密实曲线,与旋转压实一次成型得到的密实曲线作比较,以此分析温拌沥青混合料和热拌沥青混合料的压实特性。由马歇尔击实和旋转压实密实曲线、密实度斜率和密实度能量指数的分析结果表明:温拌沥青混合料用旋转压实法成型时能够体现出比热拌沥青混合料更好的可压实性,而马歇尔击实成型时则得到与之相反的结果。

关键词：公路工程马歇尔击实法旋转压实法温拌沥青混合料密实曲线

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三级民营医院护士离职原因的质性研究

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护理研究 2021年第7期35卷 1308-1310页

作者：范姜珊商临萍山西医科大学护理学院山西030001 山西医科大学第一医院

目的:深入了解民营医院护士的离职原因,为优化护理人力资源管理提供参考。方法:运用质性研究中的现象学方法,采用目的抽样,对来自山西省8所民营医院的20名离职护士进行半结构式访谈,并对访谈结果进行分析。结果:医院管理机制缺乏战略性... 详细信息

目的:深入了解民营医院护士的离职原因,为优化护理人力资源管理提供参考。方法:运用质性研究中的现象学方法,采用目的抽样,对来自山西省8所民营医院的20名离职护士进行半结构式访谈,并对访谈结果进行分析。结果:医院管理机制缺乏战略性、个体职业认同与心理授权感不足是民营医院护士离职的两大主要原因。具体表现为薪酬分配制度与职业激励机制不合理、编制鸿沟难以逾越与职业发展规划不清晰、职业认同感较低和归属感不强以及心理授权过低和医患关系紧张。结论:职业归属感不足、职业稳定性缺乏、外部工作概率较大是导致三级民营医院护士离职的主要原因。应设置人员分层管理方案、发展特色服务、鼓励公立医疗机构与社会办医疗机构有效合作,并推进公立医疗机构医务人员与民营医疗机构人员享有同等待遇的政策,避免民营医疗机构护理人员的离职。

关键词：民营医院护理管理护士离职质性研究

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