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The Observation of Ice-Nucleating Particles Active at Temperatures above –15℃ and Its Implication on Ice Formation in Clouds

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Journal of Meteorological Research 2018年第5期32卷 734-743页

作者： Kai BI Xincheng MA yunbo chen Shizuo FU Huiwen XUE Beijing Weather Modification Office(BWMO) Beijing 100089 Beijing Key Laboratory of Cloud Precipitationand Atmospheric Water ResourcesBeijing 100089 Field Experiment Base for Cloud and Precipitation Research in North China China Meteorological AdministrationBeijing 101200 Department of Atmospheric and Oceanic Sciences School of PhysicsPeking University(PKU)Beijing 100871 PKU-BWMO Joint Laboratory on Cloud and Precipitation Physics Beijing 100089 Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089

A series of measurements of ice-nucleating particles （1NPs） were performed at two sites in Beijing. At the Beijing Meteorological Service （BMS） site, which was an urban site, no INPs were found to be active above -15℃. However, at the Yanjiaping （YJP） site, which was a rural site, the concentration of 1NPs active at temperatures above -15℃ was found to be as high as 1.73 g^-1. Two parameterizations were constructed by respectively fitting the data obtained at BMS site and YJP site. The two parameterizations, as well as another parameterization from the literature, were implemented into a parcel model to investigate the effect of INPs active above -15℃ on phase partitioning in mixed-phase clouds. At a vertical velocity of 0.01 m s^-1 , which is typical for stratiform clouds associated with frontal systems, the INPs active above -15℃ nucleate ice crystals at low levels. The growth of these ice crystals remarkably reduces both the maximum liquid water mixing ratio and the altitude where the maximum liquid water mixing ratio is reached. When the vertical velocity of the parcel is increased to 0.1 m s^-l or an even higher value, the evolution of li-quid water mixing, ratio is not controlled by the INPs active above 15℃ but those active below -15℃.

关键词： ice-nucleating particles observation parcel model phase partitioning stratiform clouds

Effect of rich R-TiO2 on the rate and cycle properties of Li4Ti5O12 as anode for lithium ion batteries

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Journal of Energy Chemistry 2019年第5期28卷 182-188页

作者： Delai Qian Yijie Gu Shuainan Guo Hongquan Liu yunbo chen Juan Wang Guoxuan Ma Chuan Wu College of Materials Science and Engineering Shandong University of Science and Technology.Qingdao 266510ShandongChina Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science & EngineeringBeijing Institute of TechnologyBeijing 100081China Advanced Manufacture Technology Center China Academy of Machinery Science and TechnologyBeijing 100044China

Li4Ti5012 (LTO) with rich R-TiO2 (17.06, 23.69, and 34.42 wt%), namely, R-TiO2@Li4Ti5O12 composites, were synthesized using the hydrothermal method and tetrabutyl titanate (TBT) as the precursor. Rietveld refinement of X-ray diffraction (XRD) results show that the proportion of Li occupying 16d sites is extraordinary low and the lattice constants of LTO and R-TiO2 change with the ritanium dioxide content. EIS measurements showed that with in creasing R-TiO2 content, both its charge transfer impedance (Rct) and lithium ion diffusion coefficient (DLi) decreased. The changes of Rct and DLi caused by the increase of titanium dioxide content have synergic-antagonistic effects on the rate and cycle properties of Li4Ti5012. The rate performance is positively related to DLi, while the cycle property is negatively correlated with Rct, indicati ng that the rate performs nee is mainly related to DLi, while Rct more significantly affects the cycle performance. LTO-RT-17.06% exhibited excellent rate properties, especially under a high current density (5.0 C, 132.5 mAh/g) and LTO-RT-34.42% showed superior long-term cycle performance (0.012% capacity loss per cycle) compared to that of LTO-RT-17.06% and LTO-RT-23.69%.

关键词： Li4Ti5O12 R-TiO2 content Rate and cycle properties Charge transfer impedance Li-ion diffusion coefficient

Effects of Ginsenoside Rg1 on nuclear factor-kappa B activity in beta amyloid protein-treated neural cells

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Neural Regeneration Research 2009年第8期4卷 590-596页

作者： yunbo chen Dapeng Zhang Mei Feng Qi Wang Shuyi cheng Weixiong Liang Zehuai Wen DME Center Institute of Clinical Pharmacology Guangzhou University of Chinese Medicine. Guangzhou 510405 Guangdong Province China

BACKGROUND： Modern pharmacological studies have shown that Ginsenoside Rgl is one of the active components of ginseng that promote intelligence in the nervous system. Ginsenoside Rgl can improve memory and learning in mouse models of β-amyloid protein （Aβ）-induced dementia. OBJECTIVE： To investigate whether effects of Ginsenoside Rgl against Aβ are associated with activity of nuclear factor-kappa B （NF-κB）. DESIGN, TIME AND SETTING： The randomized performed at the DME Center, Institute of Clinica controlled, cell biological experiment was Pharmacology, Guangzhou University of Chinese Medicine, China from July 2005 to May 2006. MATERIALS： Beta-amyloid fragment 25-35 （Aβ25-35） was supplied by the Neural Biochemical Laboratory, Xuanwu Hospital, Capital Medical University, China. Ginsenoside Rgl was obtained from National Institute for the Control of Pharmaceutical and Biological Products, China. Rabbit anti-rat NF-κB p65 antibody was purchased from Santa Cruz Biotechnology, USA. METHODS： Hippocampal neurons and cortical astrocytes of neonatal Sprague Dawley rats were harvested and treated with various concentrations （0, 5, 10, 20, and 40 μmol/L） of Aβ for 6, 12, and 24 hours to establish cellular models of Alzheimer＇s disease. Cellular models were pretreated with various concentrations of Ginsenoside Rgl （1,2, 4, 8, and 16 μmol/L）. According to cell morphology and activity, the following conditions were selected： 40 μmol/L Aβ for 24 hours, as well as 2, 4, and 8 μmol/L Ginsenoside Rg1. NF-κB activity was observed using immunofluorescence and cytochemical staining. MAIN OUTCOME MEASURES： Morphology and viability of hippocampal neurons and cortical astrocytes, and activities of NF-κB were measured. RESULTS： Hippocampal neuron activity was significantly greater in the normal and 2 and 4 μmol/L Ginsenoside Rgl groups compared with the model group （P 〈 0.05）. Astrocyte activity was significantly greater in the normal, 1,2, 4, 8, and 16 μmol/L Ginsenoside Rgl groups compared

关键词： Ginsenoside Rgl Alzheimer's disease β-amyloid protein nuclear factor-κB neuroprotection

Antigenic Drift of the Hemagglutinin from an Influenza A(H1N1) pdm09 Clinical Isolate Increases its Pathogenicity In Vitro

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Virologica Sinica 2021年第5期36卷 1220-1227页

作者： Lei Xing yunbo chen Boqian chen Ling Bu Ying Liu Zhiqi Zeng Wenda Guan Qigao chen Yongping Lin Kun Qin Honglin chen Xilong Deng Xinhua Wang Wenjun Song State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory DiseaseGuangzhou Institute of Respiratory HealthThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510180China Artemisinin Research Center Guangzhou University of Chinese MedicineGuangzhou 510405China Institute of Integration of Traditional and Western Medicine The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510180China Intensive Care Unit Guangzhou No.8 People’s Hospital of Guangzhou Medical UniversityGuangzhou 510060China State Key Laboratory of Emerging Infectious Diseases Department of MicrobiologyThe University of Hong KongHong Kong SARChina China CDC National Institute for Viral Disease Control and PreventionBeijing 100052China

The influenza A(H1 N1)pdm09 virus emerged in 2009 and has been continuously circulating in humans for over ten ***,we analyzed a clinical influenza A(H1 N1)pdm09-infected patient case hospitalized for two months in Guangdong(from December 14,2019 to February 15,2020).This isolate,named A/Guangdong/LCF/2019(LCF/19),was genetically sequenced,rescued by reverse genetics,and phylogenetically analyzed in the context of other relevant pdm09 *** with earlier isolates,this pdm09 virus’s genetic sequence contains four substitutions,S186 P,T188 I,D190 A,and Q192 E,of the hemagglutinin(HA)segment at position 186–192(H3 numbering)in the epitope Sb,and two of which are located at the *** analysis indicated that the epitope Sb started undergoing a rapid antigenic change *** characterize the pathogenicity of this novel substitution motif,a panel of reassortant viruses containing the LCF/2019 HA segment or the chimeric HA segment with the four substitutions were *** growth data revealed that the reassortant viruses,including the LCF/2019 with the PTIAAQE substitution,propagated faster than those rescued ones having the STTADQQ motif in the epitope Sb in Madin-Darby Canine Kidney(MDCK)*** HI test showed that the binding activity of escape mutant to 2018 pdm09 sera was weaker than GLW/2018,suggesting that old vaccines might not effectively protect people from *** to the difference in the selection of vaccine strains,people vaccinated in the southern hemisphere could still suffer a severe infection if infected with this antigenic drift pdm09 virus.

关键词： HA antigenic drift Influenza A(H1N1)pdm09 virus HA epitope Sb

Genomic and Phenotypic Diversity of Carbapenemase-Producing Enterobacteriaceae Isolates from Bacteremia in China: A Multicenter Epidemiological, Microbiological, and Genetic Study

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Engineering 2022年第5期8卷 90-100页

作者： Beiwen Zheng Hao Xu Lihua Guo Xiao Yu Jinru Ji Chaoqun Ying yunbo chen Ping Shen Huiming Han chen Huang Shuntian Zhang Tao Lv Yonghong Xiao State Key Laboratory for Diagnosis and Treatment of Infectious Diseases Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310003China Medical College of Beihua University Jilin 132013China Department of Infectious Diseases Ningbo Medical Center Li Huili HospitalNingbo 315040China

Carbapenemase-producing Enterobacteriaceae(CPE) isolates are recognized as one of the most severe threats to public health. However, the population structure and genetic characteristics of CPE isolates among bloodstream infections(BSIs) are largely unknown. To address this knowledge gap, in this study,we included patients with clinically significant BSIs due to Enterobacterales isolates, recruited from 26 sentinel hospitals in China(2014–2015). CPE isolates were microbiologically and genomically characterized,including their susceptibility profiles, molecular typing, phylogenetic features, and genetic context analysis of carbapenemase-encoding genes. Of the 2569 BSI Enterobacterales isolates enrolled, 42(1.6%) were carbapenemase-positive. Moreover, among the 2242 investigated isolates, 1111(49.6%) extendedspectrum β-lactamase(ESBL)-producing isolates were identified in Escherichia coli(E. coli), Klebsiella pneumoniae(K. pneumoniae), Proteus mirabilis(P. mirabilis), and Klebsiella oxytoca. Whole genome sequencing analysis showed the clonal spread of K. pneumoniae carbapenemase(KPC)-2-producing K. pneumoniae sequence type(ST) 11 and New Delhi metallo-β-lactamase(NDM)-5-producing E. coli ST167 in our collection. Plasmid analysis revealed that carbapenemase-encoding genes were located on multiple plasmids. A high prevalence of biofilm-encoding type 3 fimbriae clusters and yesiniabactin-associated genes was observed in K. pneumoniae isolates. This work demonstrates the high prevalence of ESBLs and the wide dissemination of CPE among BSI isolates in China, which represent real clinical threats. Moreover, our findings first illustrate a more comprehensive genome scenario of CPE isolates among BSIs. The clonal spread of KPC-2-producing K. pneumoniae ST11 and NDM-5-producing E. coli ST167 needs to be closely monitored.

关键词： Carbapenemase Carbapenemase-producing Enterobacteriaceae Plasmid-mediated China Extended-spectrum b-lactamase

Analysis of the origin of peak aerosol optical depth in springtime over the Gulf of Tonkin

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Journal of Environmental Sciences 2016年第2期28卷 129-137页

作者： Xiaoli Shan Jun Xu Yixue Li Feng Han Xiaohui Du Jingying Mao yunbo chen Youjiang He Fan Meng Xuezhi Dai College of Resources and Environment Shandong Agricultural University Taian 271000 China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012 China College of Environmental Science and Engineering Taiyuan University of Technology Taiyuan 030024 China College of Geography and Environment Shandong Normal University Jinan 250014 China Environmental Protection Research Institute of Guangxi Nanning 530022 China

By aggregating MODIS（moderate-resolution imaging spectroradiometer） AOD（aerosol optical depth） and OMI（ozone monitoring instrument） UVAI（ultra violet aerosol index）datasets over 2010–2014, it was found that peak aerosol loading in seasonal variation occurred annually in spring over the Gulf of Tonkin（17–23°N, 105–110°E）. The vertical structure of the aerosol extinction coefficient retrieved from the spaceborne lidar CALIOP（cloud-aerosol lidar with orthogonal polarization） showed that the springtime peak AOD could be attributed to an abrupt increase in aerosol loading between altitudes of 2 and 5 *** contrast, aerosol loading in the low atmosphere（below 1 km） was only half of that in winter. Wind fields in the low and high atmosphere exhibited opposite transportation patterns in spring over the Gulf of Tonkin, implying different sources for each level. By comparing the emission inventory of anthropogenic sources with biomass burning, and analyzing the seasonal variation of the vertical structure of aerosols over the Northern Indo-China Peninsula（NIC）, it was concluded that biomass burning emissions contributed to high aerosol loading in spring. The relatively high topography and the high surface temperature in spring made planetary boundary layer height greater than 3 km over NIC. In addition, small-scale cumulus convection frequently occurred, facilitating pollutant rising to over 3 km, which was a height favoring long-range transport. Thus, pollutants emitted from biomass burning over NIC in spring were raised to the high atmosphere, then experienced long-range transport, leading to the increase in aerosol loading at high altitudes over the Gulf of Tonkin during spring.

关键词： Gulf of Tonkin Aerosol optical depth Aerosol vertical structure Biomass burning Transportation

Characterization of wavy root 1,an agravitropism allele,reveals the functions of OsPIN2 in fine regulation of auxin transport and distribution and in ABA biosynthesis and response in rice(Oryza sativa L.)

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The Crop Journal 2022年第4期10卷 980-992页

作者： Wenqiang Li Minjuan Zhang Lei Qiao yunbo chen Dapeng Zhang Xiuqing Jing Pengfei Gan Yangbin Huang Junru Gao Wenting Liu Chunhai Shi Hongchang Cui Haifeng Li Kunming chen State Key Laboratory of Crop Stress Biology in Arid Areas College of Life SciencesNorthwest A&F UniversityYangling 712100ShaanxiChina The Sericultural and Silk Research Institute College of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100ShaanxiChina College of Agronomy Northwest A&F UniversityYangling 712100ShaanxiChina Department of Agronomy College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058ZhejiangChina Department of Biological Science Florida State UniversityTallahasseeFL 32306USA Coconut Research Institute of Chinese Academy of Tropical Agricultural Sciences Wenchang 571339HainanChina

Root system architecture is influenced by *** the root senses gravity and directs its orientation,so-called gravitropism,is not only a fundamental question in plant biology but also theoretically important for genetic improvement of crop root ***,the mechanism has not been elucidated in most *** characterized a rice agravitropism allele,wavy root 1(war1),a loss-of-function allele in OsPIN2,which encodes an auxin efflux *** loss of OsPIN2 function,war1 leads to altered root system architecture including wavy root,larger root distribution angle,and shallower root system due to the loss of gravitropic perception in root *** the war1 mutant,polar auxin transport was disrupted in the root tip,leading to abnormal auxin levels and disturbed auxin transport and distribution in columella *** sedimentation,an important process in gravitropic sensing,was also decreased in root tip columella *** results indicated that OsPIN2 controls gravitropism by finely regulating auxin transport,distribution and levels,and amyloplast sedimentation in root *** identified a novel role of OsPIN2 in regulating ABA biosynthesis and response *** of OsPIN2 function in the war1 resulted in increased sensitivity to ABA in seed germination,increased ABA level,changes in ABA-associated genes in roots,and decreased drought tolerance in the *** results suggest that the auxin transporter OsPIN2 not only modulates auxin transport to control root gravitropism,but also functions in ABA signaling to affect seed germination and root development,probably by mediating crosstalk between auxin and ABA pathways.

关键词： Auxin transporter Root development Wavy root Gravitropism Abscisic acid(ABA) Drought tolerance

劳工NGO的微博赋权分析:以深圳“小小草”遭遇逼迁事件为例

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国际新闻界 2014年第11期36卷 51-64页

作者：陈韵博暨南大学新闻与传播学院

本文以深圳"小小草"工友家园这一劳工NGO为研究对象,采用在线民族志和深度访谈等研究方法,通过分析他们在遭遇逼迁过程中的新媒体实践过程和结果,总结微博在事件中的作用和赋权的效果。研究发现,微博起到了直播事态发展、与传统媒体互... 详细信息

本文以深圳"小小草"工友家园这一劳工NGO为研究对象,采用在线民族志和深度访谈等研究方法,通过分析他们在遭遇逼迁过程中的新媒体实践过程和结果,总结微博在事件中的作用和赋权的效果。研究发现,微博起到了直播事态发展、与传统媒体互动、利用"话题"功能进行深入探讨和社会动员等作用,同时在个体、人际和社会参与三个层面都实现了不同程度的赋权。文末还讨论了微博在劳工NGO

关键词：劳工NGO 新媒体微博赋权

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机械工程材料优选方法的研究现状

机械工程学报 2007年第1期43卷 19-24页

作者：陈蕴博岳丽杰机械科学研究院材料工程研究所北京100083 山东科技大学材料科学与工程学院青岛266510

在综述现代机械工程材料选择方法最新研究进展的基础上,通过列举现代选材方法在工程中的具体应用实例,概述了选择工程材料时应考虑的因素,并对不同选材方法及其特点进行综合评价和优化。提出采用构件的失效抗力指标进行选材的方法,变革... 详细信息

在综述现代机械工程材料选择方法最新研究进展的基础上,通过列举现代选材方法在工程中的具体应用实例,概述了选择工程材料时应考虑的因素,并对不同选材方法及其特点进行综合评价和优化。提出采用构件的失效抗力指标进行选材的方法,变革选材的传统习惯,使选材向科学化和量值化转变,具有重要的实用价值。此外,结合建立机械工程材料共享数据库平台和专家咨询系统的研究实践,指明材料数据库及专家咨询系统在选材方面的作用和效益,可为用户快速、全面地查找材料信息提供帮助。

关键词：工程材料选材方法材料数据库