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| 1 | δ^(15)N-stable isotope analysis of NH_(x): An overview on analytical measurements, source sampling and its source apportionment显示文摘Agricultural sources and non-agricultural emissions contribute to gaseous ammonia(NH_(3))that plays a vital role in severe haze formation.Qualitative and quantitative contributions of these sources to ambient PM_(2.5)(particulate matter with an aerodynamic equivalent diameter below 2.5µm)concentrations remains uncertain.Stable nitrogen isotopic composition(δ^(15)N)of NH_(3)and NH_(4)+(δ^(15)N(NH_(3))andδ^(15)N(NH_(4)+),respectively)can yield valuable information about its sources and associated processes.This review provides an overview of the recent progress in analytical techniques forδ^(15)N(NH_(3))andδ^(15)N(NH_(4)+)measurement,sampling of atmospheric NH_(3)and NH_(4)+in the ambient air and their sources signature(e.g.,agricultural vs.fossil fuel),and isotope-based source apportionment of NH_(3)in urban atmosphere.This study highlights that collecting sample that are fully representative of emission sources remains a challenge in fingerprintingδ^(15)N(NH_(3))values of NH_(3)emission sources.Furthermore,isotopic fractionation during NH_(3)gas-to-particle conversion under varying ambient field conditions(e.g.,relative humidity,particle pH,temperature)remains unclear,which indicates more field and laboratory studies to validate theoretically predicted isotopic fractionation are required.Thus,this study concludes that lack of refinedδ^(15)N(NH_(3))fingerprints and full understanding of isotopic fractionation during aerosol formation in a laboratory and field conditions is a limitation for isotope-based source apportionment of NH_(3).More experimental work(in chamber studies)and theoretical estimations in combinations of field verification are necessary in characterizing isotopic fractionation under various environmental and atmospheric neutralization conditions,which would help to better interpret isotopic data and our understanding on NH_(x)(NH_(3)+NH_(4)+)dynamics in the atmosphere. | Noshan Bhattarai Shuxiao Wang Yuepeng Pan Qingcheng Xu Yanlin Zhang Yunhua Chang Yunting Fang | 2021 | Frontiers of Environmental Science & Engineering2021，15，6： | 3 |
| 2 | Effectiveness of intravenous r- tPA versus UK for acute ischaemic stroke: a nationwide prospective Chinese registry study显示文摘Background Intravenous recombinant tissue plasminogen activator(r-tPA)and urokinase(UK)are both recommended for the treatment of acute ischaemic stroke(AIS)in China,but with few comparative outcome data being available.We aimed to compare the outcomes of these two thrombolytic agents for the treatment of patients within 4.5 hours of onset of AIS in routine clinical practice in China.Methods A pre-planned,prospective,nationwide,multicentre,real-world registry of consecutive patients with AIS(age≥18 years)who received r-tPA or UK within 4.5 hours of symptom onset according to local decision-making and guideline recommendations during 2017-2019.The primary effectiveness outcome was the proportion of patients with an excellent functional outcome(defined by modified Rankin scale scores 0 to 1)at 90 days.The key safety endpoint was symptomatic intracranial haemorrhage according to standard definitions.Multivariable logistic regression was used for comparative analysis,with adjustment according to propensity scores to ensure balance in baseline characteristics.Results Overall,4130 patients with AIS were registered but 320 had incomplete or missing data,leaving 3810 with available data for analysis of whom 2666 received r-tPA(median dose 0.88(IQR 0.78-0.90)mg/kg)and 1144 received UK(1.71(1.43-2.00)×104 international unit per kilogram).There were several significant intergroup differences in patient characteristics:r-tPA patients were more educated,had less history of stroke,lower systolic blood pressure,greater neurological impairment and shorter treatment times from symptom onset than UK patients.However,in adjusted analysis,the frequency of excellent outcome(OR 1.18,95%CI 1.00 to 1.40,p=0.052)and symptomatic intracranial haemorrhage(OR 0.70,95%CI 0.33 to 1.47,p=0.344)were similar between groups.Conclusions UK may be as effective and carry a similar safety profile as r-tPA in treating mild to moderate AIS within guidelines in China.Registration http://www.clinicaltrials.gov.unique identifier:NCT02854592. | Xinhong Wang Xiaoqiu Li Yuming Xu Runhui Li Qingcheng Yang Yong Zhao Fengyun Wang Baoying Sheng Runqing Wang Shaoyuan Chen Lihua Wang Liying Shen Xiaowen Hou Yu Cui Duolao Wang Bin Peng Craig S Anderson Huisheng Chen On behalf of INTRECIS Investigators | 2021 | Stroke & Vascular Neurology2021，6，4： | 2 |
| 3 | Modified methods for isolation of pancreatic stellate cells from human and rodent pancreas显示文摘Primary cultures of pancreatic stellate cells(PSCs) remain an important basis for in vitro study.However,effective methods for isolating abundant PSCs are currently lacking.We report on a novel approach to isolating PSCs from normal rat pancreases and human pancreatic ductal adenocarcinoma(PDAC) tissue.After anaesthesia and laparotomy of the rat,a blunt cannula was inserted into the pancreatic duct through the anti-mesentery side of the duodenum,and the pancreas was slowly infused with an enzyme solution until all lobules were fully dispersed.The pancreas was then pre-incubated,finely minced and incubated to procure a cell suspension.PSCs were obtained after the cell suspension was filtered,washed and subject to gradient centrifugation with Nycodenz solution.Fresh human PDAC tissue was finely minced into 1×1×l mm^3 cubes with sharp blades.Tissue blocks were placed at the bottom of a culture plate with fresh plasma(EDTA-anti-coagulated plasma from the same patient,mixed with CaCL) sprinkled around the sample.After culture for 5-10 days under appropriate conditions,activated PSCs were harvested.An intraductal perfusion of an enzyme solution simplified the procedure of isolation of rat PSCs,as compared with the multiple injections technique,and a modified outgrowth method significantly shortened the outgrowth time of the activated cells.Our modification in PSC isolation methods significantly increased the isolation efficiency and shortened the culture period,thus facilitating future PSC-related research. | Liangtao Zhao Baobao Cai Zipeng Lu Lei Tian Song Guo Pengfei Wu Dong Qian Qingcheng Xu Kuirong Jiang Yi Miao | 2016 | The Journal of Biomedical Research2016，30，6： | 1 |
| 4 | Effects of natural forest conversion and plantation tree species composition on soil macrofauna communities in Northeast China mountains显示文摘As primary and secondary forests are being replaced by plantations across the globe,the soil macrofauna community structure is also affected,but little is known about the impact of mixed culture plantations compared with monocultures on the soil macrofauna.To determine the impact of forest conversion on soil macrofauna,we surveyed the soil macrofauna in two broad-leaved and three coniferous monoculture stands and four coniferous-broadleaved mixed stands,and in adjacent reserved secondary stands as a reference.Soil macro fauna community composition was significant affected by forest type,season and their interaction(P<0.05).The abundance,taxa richness and diversity of soil macro fauna changed to different degrees depending on the plantation type.Broadleaved monoculture stands and secondary stands had similar macrofauna abundance and taxa richness,but values were lower in coniferous stands than in secondary stands.The Shannon index for macrofauna in coniferous stands was also the lowest,but the Pielou index did not differ between forest types.The negative effects of the conifer monoculture on soil macro fauna were not present in the mixed stands with broad-leaved trees.Forest conversion impacted soil properties;soil moisture,NO_(3)^(-),and pH were significant drivers of soil macrofauna community structure.The impact of forest conversion on soil macrofauna was closely dependent on tree species composition and diversity.The macro fauna community structure in the broadleaved and the mixed stands were relatively similar to that in the natural forest,and thus recommended for forest conversion in the study area. | Shuangjiao Ma Qingcheng Wang Yong Zhang Limei Yan Donghai Cui Liqing Xu | 2023 | Journal of Forestry Research2023，34，5： | 0 |
| 5 | Defect evolution in GaN thin film heterogeneously integrated with CMOS-compatible Si(100)substrate by ion-cutting technology显示文摘Ion-cutting technology is an ingenious solution to the highquality heterogeneous integration of Ga N thin films with CMOS-compatible Si(100)substrate,which provides a platform to combine Ga N-based optoelectronics,high-frequency and high-power electronics with digital signal processing,logic computation,and control of Si(100)CMOS[1]. | Hangning SHI Ailun YI Jiaxin DING Xudong LIU Qingcheng QIN Juemin YI Junjie HU Miao WANG Demin CAI Jianfeng WANG Ke XU Fengwen MU Tadatomo SUGA RenéHELLER Mao WANG Shengqiang ZHOU Wenhui XU Kai HUANG Tiangui YOU Xin OU | 2023 | Science China(Information Sciences)2023，66，11： | 0 |
| 6 | Multifunctional design of single-atom catalysts for multistep reactions显示文摘With the merits of high atom utilization,low cost,unique and tunable microstructures,as well as the particular catalytic behaviors,single-atom catalysts(SACs)have gained worldwide interest and achieved great advancements in heterogeneous catalysis recently.However,catalyzing an intricate multistep reaction is usually challenging for one single-atom center,in which case multiple catalytic sites are needed.In this review,the experimental and computational advances in the construction strategies of multi-active-site SACs will be summarized and classified as single-atom/single-atom,single-atom/nanoparticle and single-atom/support multifunctional catalysts.The microstructures of different active centers and their catalytic behaviors during catalysis will be emphatically highlighted.Moreover,the confronting challenges and opportunities of this field will be discussed.This review will place emphasis on the design of multifunctional SACs for multistep reactions,which will shed light on their further development in heterogeneous catalysis and beyond. | Zechuan Xu Qingcheng Zhang Zaimei Huang Heng Chen Jian Zhang Wei Chen Ge Meng Dingsheng Wang | 2023 | Science China Chemistry2023，66，5： | 0 |
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