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Organic nitrogen in PM2.5 in Beijing

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Frontiers of Environmental Science & Engineering 2015年第6期9卷 1004-1014页

作者： Qian ZHANG Fengkui DUAN Kebin HE Yongliang MA Haiyan LI Takashi KIMOTO aihua zheng State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Tsinghua University Beijing 100084 China Kimoto Electric Co. Ltd. Funahashi-Cho Tennouji-Ku Osaka 543-0024 Japan Analysis and Testing Center of Beijing Normal University Beijing 100875 China

Nitrogenous species, as important chemical components in PM2.5, include organic nitrogen （ON） and inorganic nitrogen （IN）, both of which have potential effects on human health, climate change and visibility degradation. In this study, we analyzed total nitrogen （TN） by CHN Elemental analyzer and inorganic nitrogen by ion chromatography （IC） respectively to obtain ON by calculating the difference between TN and IN. The results show that the mean ON concentrations in winter and summer are both 2.86 μg. m-a, ten times higher than other places reported on average. ON contributes about 20%- 30% to TN on average in both seasons, presenting higher contribution in summer. N：C ratios are much higher in summer than winter. ON sources or formation were strengthened by heavy PM2.5 pollution loads, especially sensitive to sulfate. ON concentrations are higher at night in the both seasons, however with distinguished day and night difference patterns influenced by relative humidity （RH） conditions. In winter, ON concentrations increase with RH on average through low RH values to high RH values. The variations are far larger than the ones caused by day and night difference. However in summer, day and night difference dominates the variations of ON concen- trations at low RH values, and RH conditions promote ON concentrations increase significantly only at high RH values. Dust related source and anthropogenic emission related secondary source are identified as important sources for ON. At heavy pollution loads, ON sources are more of secondary formation, possibly strengthened by combination influence of RH and acidity increase.

关键词： organic nitrogen N:C ratio secondary dayand night variation relative humidity (RH) acidity

Graphene oxide and molecular beacons-based multiplexed DNA detection by synchronous fluorescence analysis

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Science China Chemistry 2013年第3期56卷 380-386页

作者： XIANG DongShan zheng aihua LUO Ming JI XingHu HE ZhiKe Key Laboratory of Analytical Chemistry for Biology and Medicine(Ministry of Education) College of Chemistry and Molecular Sciences Wuhan University

We have developed a multiplexed DNA detection method based on graphene oxide(GO) and molecular beacons(MBs) by synchronous fluorescence analysis,demonstrated it by an oligonucleotide sequence of wild-type HBV(T1) and a reverse-transcription oligonucleotide sequence of the RNA fragment of HIV(T2) as a model *** the absence of targets DNA,FAM-tagged free MB probes(P HBV) and ROX-tagged free MB probes(P HIV) are adsorbed on GO via-interactions between DNA nucleobases and nucleosides,and the-rich GO brings the fluorophores of MB and GO into close *** then,the fluorescence of fluorophores is quenched by *** in the presence of targets DNA,P HBV and P HIV hybridize with their targets DNA resulting in the formation of double-stranded DNA(dsDNA),causing the separation of P HBV and P HIV from the surface of GO and the recovery of the fluorescence of fluorophores(FAM and ROX) *** simultaneous detection of T1 and T2 can be realized by measuring fluorescence signals of FAM and ROX,*** the optimum conditions,the fluorescence intensities of two dyes all exhibit good linear dependence on their target DNA concentration in the range of 5×10-11-5×10-9 *** detection limit of T1 is 3×10-11 M(3),and that of T2 is 2×10-11 *** with other methods for DNA detection based on GO,the proposed method has some advantages including higher selectivity and shorter analytical time.

关键词： multiplexed DNA molecular beacons synchronous fluorescence analysis graphene oxide

Entry of severe fever with thrombocytopenia syndrome virus

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Virologica Sinica 2017年第1期32卷 44-50页

作者： Fei Yuan aihua zheng CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of Microbiology Chinese Academy of Sciences State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of Sciences

Severe fever with thrombocytopenia syndrome virus （SFTSV） is a globe-shaped virus covered by a dense icosahedral array of glycoproteins Gn/Gc that mediate the attachment of the virus to host cells and the fusion of viral and cellular membranes. Several membrane factors are involved in virus entry, including C-type lectins and nonmuscle myosin heavy chain IIA. The post-fusion crystal structure of the Gc protein suggests that it is a class II membrane fusion protein, similar to the E/E1 protein of flaviviruses and alphaviruses. The virus particles are internalized into host cell endosomes through the clathrin-dependent pathway, where the low pH activates the fusion of the virus with the cell membrane. With information from studies on other bunyaviruses, herein we will review our knowledge of the entry process of SFTSV.

关键词： severe fever with thrombocytopenia syndrome virus (SFTSV) bunyavirus entry fusion receptor

Empirical Test of Determinants of Accepting Mobile Payment

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China Communications 2012年第7期9卷 127-141页

作者： Zhang aihua Yue Xing zheng Mingxing School of Economics and Management Beijing University of Posts and Telecommunications Beijing 100876P. R. China

From a global perspective, the develop ment of 3G services in China is quite different from other countries. The factors that influence users＇ adoption of mobile payment are worth ex ploring. This study employs the Technology Ac ceptance Model （TAM） to examine determinant factors affecting consumers＇ acceptance intentions of mobile payment. We adopt Hofstede＇s cultural dimensions as moderators to extend the TAM model for exploring the impact of uncertainty a voidance on mobile payment acceptance.

关键词： mobile payment Hofstede TAM uncertainty avoidance

Infection and transovarial transmission of severe fever with thrombocytopenia syndrome virus in Rhipicephalus sanguineus in Hainan Island,China

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Integrative Zoology 2023年第6期18卷 1009-1013页

作者： Chuanfei YUAN Yajun LU Jinqian LI Chen CHEN Yanhong WANG aihua zheng Zhen ZOU Qianfeng XIA Key Laboratory of Tropical Translational Medicine of Ministry of Education NHC Key Laboratory of Tropical Disease ControlSchool of Tropical MedicineHainan Medical UniversityHaikouHainanChina State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina

Dear Editor,Severe fever with thrombocytopenia syndrome(SFTS)is an emerging human disease with high mortality rates of up to 30%(Yu et al.2011;Li et al.2018,2021).The increasing incidence of SFTS led to great concern for public health in East Asia(Zhu et al.2019;Miao et al.2020).SFTS is caused by SFTS virus(SFTSV),a newly discovered tick-borne bunyavirus in the family *** was first identified in China in 2009(Yu et al.2011)and subsequently in South Korea(Kim et al.2013)and Japan(Takahashi et al.2014).

关键词： fever mortality

Infection of SARS-CoV-2 causes severe pathological changes in mouse testis

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Journal of Genetics and Genomics 2023年第2期50卷 99-107页

作者： Min Chen Shihua Li Shujun Liu Yuhang Zhang Xiuhong Cui Limin Lv Bowen Liu aihua zheng Qihui Wang Shuguang Duo Fei Gao State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China University of Chinese Academy of Sciences Beijing 100101China CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Institute of Zoology Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing 100101China

Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARSCoV-2),has affected more than 600 million people *** organs including lung,intestine,and brain are infected by *** has been reported that SARS-CoV-2 receptor angiotensin-converting enzyme-2(ACE2)is expressed in human ***,whether testis is also affected by SARS-CoV-2 is still *** this study,we generate a human ACE2(hACE2)transgenic mouse model in which the expression of hACE2 gene is regulated by hACE2 *** and Leydig cells from hACE2 transgenic mice can be infected by SARS-CoV-2 pseudovirus in vitro,and severe pathological changes are observed after injecting the SARS-CoV-2 pseudovirus into the seminiferous *** studies reveal that Sertoli and Leydig cells from hACE2 transgenic mice are also infected by authentic SARS-CoV-2 virus in *** testis interstitium injection,authentic SARS-CoV-2 viruses are first disseminated to the interstitial cells,and then detected inside the seminiferous tubules which in turn cause germ cell loss and disruption of seminiferous *** study demonstrates that testis is most likely a target of SARS-CoV-2 *** should be paid to the reproductive function in SARS-CoV-2 patients.

关键词： SARS-CoV-2 ACE2 Sertoli cell Leydig cell Testis

Rapid Determination Method of Trace Sulfate in Radar Coolant by ion chromatography

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Rapid Determination Method of Trace Sulfate in Radar Coolant...

An antibody cocktail with broadened mutational resistance and effective protection against SARS-CoV-2

第七届全国仪器分析及样品预处理学术研讨会

作者： zheng aihua Analytical ＆ Testing Center of Beijing Normal University

Arapid determination method for trace sulfate ion in radar ethylene glycol coolants by ion chromatography was set up in the article. Determined using 200μl large sample quantitative volume, With sample diluted at least 19+1（v/v） or greater, and gradient elution, a large amount of interference substance were eliminated , Then using Dionex-600 ion chromatography system including separate column IonPacAS11（4x250mm） and guard column IonPacAG11（4x50mm） suppressor and detector determined the trace sulfate content in the sample, By optimizing the chromatographic conditions including flow rate and eluent concentration, Several other common anions, which are fluoride、chloride 、nitrite、nitrate、phosphate and organic acids can be separated . When the concentration of sulfate was in the range from 0.1mg/L to 10mg/L, the regression coefficient was 0.9999. The relative standard deviation of sulfate ion is 2.4% （n=9）, The detection limit is 0.05mg/L. This method is simple in operation and can be finished in 18 min. As a result the determination of trace sulfate in radar coolant by IC is practicality and promote meaningful.

关键词： ion chromatography trace sulfate radar ethylene glycol coolants

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Science China(Life Sciences) 2023年第1期66卷 165-179页

作者： Chunyun Sun Hang Chi Fei Yuan Jing Li Ji Yang aihua zheng Fei Wang Lingling Sun Yanjing Zhang Ping Hu Lihua Jiao Yongqiang Deng Liangzhi Xie Beijing Engineering Research Center of Protein and Antibody Sinocelltech Ltd.Beijing 100176China Department of Virology State Key Laboratory of Pathogen and BiosecurityBeijing Institute of Microbiology and EpidemiologyAcademy of Military Medical SciencesBeijing 100071China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Key Laboratory of Monoclonal Antibody Research and Development Sino Biological Inc.Beijing 100176China Cell Culture Engineering Center Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100005China

Neutralizing antibodies have been proven to be highly effective in treating mild and moderate COVID-19 patients,but continuous emergence of SARS-CoV-2 variants poses significant *** cocktail treatments reduce the risk of escape mutants and *** this study,a new cocktail composed of two highly potent neutralizing antibodies(HB27 and H89Y)was developed,whose binding epitope is different from those cocktails that received emergency use *** cocktail showed more potent and balanced neutralizing activities(IC_(50)0.9–11.3 ng mL^(-1))against a broad spectrum of SARS-CoV-2 variants over individual HB27 or H89Y ***,the cocktail conferred more effective protection against the SARS-CoV-2 Beta variant in an aged murine model than *** was shown to prevent SARS-CoV-2 mutational escape in vitro and effectively neutralize 61 types of pseudoviruses harbouring single amino acid mutation originated from variants and escape strains of Bamlanivimab,Casirivimab and Imdevimab with IC_(50)of 0.6–65 ng mL^(-1).Despite its breadth of variant neutralization,the HB27+H89Y combo and EUA cocktails lost their potencies against Omicron *** results provide important insights that new antibody cocktails covering different epitopes are valuable tools to counter virus mutation and escape,highlighting the need to search for more conserved epitopes to combat Omicron.

关键词： SARS-CoV-2 COVID-19 epitopes antibody cocktail mutational escape

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Fine particulate matter(PM_(2.5)/PM_(1.0)) in Beijing,China: Variations and chemical compositions as well as sources

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Journal of Environmental Sciences 2022年第11期34卷 187-198页

作者： Lining Luo Xiaoxuan Bai Shuhan Liu Bobo Wu Wei Liu Yunqian Lv Zhihui Guo Shumin Lin Shuang Zhao Yan Hao Jiming Hao Kai Zhang aihua zheng Hezhong Tian State Key Laboratory of Environmental Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing 100875China Center for Atmospheric Environmental Studies Beijing Normal UniversityBeijing 100875China School of Environment Tsinghua UniversityBeijing 100084China Department of Environmental Health Sciences School of Public Health University at Albany State University of New York One University Place RensselaerNY 12144USA Analysis and Testing Center Beijing Normal UniversityBeijing 100875China

Particulate matter(i.e.,PM_(1.0) and PM_(2.5)),considered as the key atmospheric pollutants,exerts negative effects on visibility,global climate,and human health by associated chemical ***,our understanding of PM and its chemical compositions in Beijing under the current atmospheric environment is still not complete after witnessing marked alleviation during 2013–*** measurements can be crucial for further air quality improvement by better characterizing PM pollution and chemical compositions in ***,we conducted simultaneous measurements on PM in Beijing during 2018–*** indicate that annualmean PM_(1.0) and PM_(2.5) concentrations were 35.49±18.61μg/m^(3) and 66.58±60.17μg/m^(3),showing a positive response to emission *** contribution of sulfate,nitrate,and ammonium(SNA)played an enhanced role with elevated PM loading and acted as the main contributors to pollution *** observed among chemical species between PM_(1.0) and PM_(2.5) in spring suggest that sand particles trend to accumulate in the range of 1–2.5μ*** episodes occurred accompanied with southerly clusters and high formation of SNA by heterogeneous reactions in summer and winter,*** from positive matrix factorization(PMF)combined with potential source contribution function(PSCF)models showed that potential areas were seasonal dependent,secondary and vehicular sources became much more important compared with previous studies in *** study presented a continuous investigation on PM and sources origins in Beijing,which provides a better understanding for further emission control as well as a reference for other cities in developing countries.

关键词： Fine particles Haze Chemical species Seasonal variation Source apportionment