检索结果-南通市图书馆

Green synthesis and Catalysis 2024年第1期5卷 57-61页

作者： Lesong Li tao Liu Weiwu Ren y.ng Wang Molecular synthesis Center&Key Laboratory of Marine Drugs Chinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Qingdao National Laboratory for Marine Science and Technology(QNLM)Qingdao 266237China

A catalyst-free and atom-economical[4+3]cycloaddition of azadienes with C,n-cyclic azomethine imines has been developed,providing an efficient and environmentally benign access to 1,2,4-triazepines with high diastereo... 详细信息

关键词： Catalyst-free Atom-economical[4+3] Cycloaddition C,n-cyclic Azomethine imine Azadiene 1,2,4-triazepine

naturally occurring PA^(E206K)point mutation in 2009 H1n1 pandemic influenza viruses impairs viral replication at high temperatures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Virologica sinica 2024年第1期39卷 71-80页

作者： Mengmeng Cao Qiannan Jia Jinghua Li Lili Zhao Li zhu yufan Zhang shan Li tao Deng national Institute of Pathogen Biology Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing100730China CAs Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing100101China

The emergence of influenza virus A pandemic H1n1 in April 2009 marked the first pandemic of the 21st *** this study,we observed significant differences in the polymerase activities of two clinical 2009 H1n1 influenza A virus isolates from Chinese and Japanese *** comparison of the three main protein subunits(PB2,PB1,and PA)of the viral RnA-dependent RnA polymerase complex and subsequent mutational analysis revealed that a single amino acid substitution(E206K)was responsible for the observed impaired replication *** in vitro experiments showed that presence of PAE206K decreased the replication of influenza A/Wsn/33 virus in mammalian cells and a reduction in the virus’s pathogenicity in *** studies revealed that PAE206K is a temperature-sensitive mutant associated with the inability to transport PB1–PA complex to the nucleus at high temperature(39.5℃).Hence,this naturally occurring variant in the PA protein represents an ideal candidate mutation for the development of live attenuated influenza vaccines.

关键词： H1n1 Influenza A virus Polymerase acidic protein Point mutation Viral replication

Weather influenced nestling growth of an insectivorous but not a granivorous grassland passerine in Argentina

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Avian Research 2024年第2期15卷 156-162页

作者： Martín Alejandro Colombo Adrian Jauregui Luciano n.segura Laboratorio de Ecología de Aves.Institute“Dr.Raúl A.Ringuelet”(ILPLA)-UnLP/COnICET Boulevard 1201437La PlataB1900Buenos AiresArgentina

nestling growth of birds can be affected by weather *** general,it is expected that higher temper-atures favor growth by improving food availability and nestling metabolism,while rain hinders it by reducing foraging ***,most of these patterns have been described in insectivorous cavity.nesting birds in temperate *** tested these predictions in two neotropical grassland ground-nesting birds with contrasting nestling diets and therefore potentially different responses to *** measured nestlings of the Hellmayr’s Pipit(Anthus hellmayri,an insectivorous passerine)and the Grassland yellow-Finch(sicalis luteola,which feeds its nestlings exclusively with seeds)during three breeding seasons(2017-2020)in central-eastern *** took measurements of tarsus and body mass,modeled growth curves using nonlinear mixed-effects models,and evaluated the effects of minimum daily temperature and precipitation during the growth period and the 30 days prior to *** pipits(60 nestlings from 21 nests),minimum temperatures during the growth period were positively associated with tarsus and body mass ***,there was a positive association between precipitation during the pre-hatching period and tarsus ***,none of the weather variables analyzed had significant effects on nestling growth of finches(131 nestlings from 35 nests).Dietary contrast between species may explain the different *** activity and abundance can be affected by weather variations within the span of a breeding season,whereas seeds may depend on conditions from previous years,making the effects harder to *** with reduced asymptotic size can have reduced chances of ***,pipit populations could be impacted if they experience cold and dry conditions during their breeding season,which is of major relevance in the current context of climate change.

关键词： Finches Grassland birds neotropical birds Pipits Precipitation Temperature

engineering and understanding sns_(0.5)se_(0.5)@n/s/se triple-doped carbon nanofibers for enhanced sodium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 226-230页

作者： Fanjun Kong yixin Ge shi tao Zhengqiu yuan Chen Lu Zhida Han Lianghao yu Bin Qian school of Electronic and Information engineering Changshu Institute of TechnologyChangshu 215500China Key Laboratory of spin Electron and nanomaterials of Anhui Higher Education Institutes Suzhou UniversitySuzhou 234000China Far East Holding Group Co. Ltd.Yixing 214200China

Tin-based chalcogenides have attracted tremendous attention as an anode material for sodium storage owing to their unique structure and high theoretical capacity. Unfortunately, the large volume change and poor conductivity lead to sluggish reaction kinetics and poor cycling performance. Herein, sns_(0.5)se_(0.5)nanoparticles coupled with n/s/se triple-doped carbon nanofibers(sns_(0.5)se_(0.5)@nsse-C) are designed and synthesized through electrospinning and annealing process. Benefiting from the synergistic effects of sns_(0.5)se_(0.5)and nsse-C, the sns_(0.5)se_(0.5)@nsse-C nanofibers exhibit a high reversible capacity and ultralong cycle life at higher current density for sodium-ion batteries. Furthermore, the sodium storage mechanism and electrochemical reaction kinetics of the sns_(0.5)se_(0.5)@nsse-C composite are characterized by the in-situ measurements. The theoretical calculations further reveal the structural advantages of sns_(0.5)se_(0.5)@nsseC composite, which exhibits a high adsorption energy of na+. This work can provide a novel idea for the synthesis of ternary tin-based chalcogenides and is beneficial for the investigation of their reaction kinetics.

关键词： sns_(0.5)se_(0.5) Carbon nanofibers Doping Density functional theory sodium ion batteries

Risk factors for recurrence of common bile duct stones after surgical treatment and effect of ursodeoxycholic acid intervention

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal surgery 2024年第1期16卷 103-112页

作者： Wei-Hong yuan Zheng Zhang Qi Pan Bo-neng Mao tao yuan Department of Gastroenterology Yixing People’s HospitalYixing 214200Jiangsu ProvinceChina

BACKGROUnD Endoscopic retrograde cholangiopancreatography(ERCP)is an accurate diagnostic method for choledocholithiasis and treatment option for stone ***,ursodeoxycholic acid(UDCA)can dissolve cholesterol stones and prevent their development and reappearance by lowering the cholesterol concen-tration in *** these treatment options,there are still patients who experience stone *** clinical data of 100 patients with choledochal stones who were hospitalized at the yixing People’s Hospital and underwent ERCP for successful stone extraction between June 2020 and December 2022 were retrospectively *** to the post-ERCP treatment plan,100 patients were classified into UDCA(n=47)and control(n=53)*** aimed to assess the clinical efficacy and rate of relapse in the two patient *** then collected information(basic demographic data,clinical characteristics,and serum biochemical indicators)and determined the factors contributing to relapse using logistic regression *** secondary goal was to determine the effects of UDCA on liver function after *** to the control group,the UDCA group demonstrated a higher clinical effectiveness rate of 92.45%vs 78.72%(Pno significant differences were observed in liver function indices,including total bilirubin,direct bilirubin,gamma-glutamyl transpeptidase,alanine aminotransferase,alkaline phosphatase,and aspartate aminotransferase,between the two groups before *** treatment,all liver function indices were significantly *** the control vs UDCA groups,the UDCA group exhibited significantly lower levels of all indices(55.39±6.53 vs 77.31±8.52,32.10±4.62 vs 45.39±5.69,142.32±14.21 vs 189.63±16.87,112.52±14.25 vs 149.36±15.36,122.61±16.00 vs 171.33±22.09,96.98±10.44 vs 121.35±11.57,respectively,all Pstone recurrence rate was lower in the UDCA group(13.21%)in contrast with the control group(44.68%).Periampullary divertic

关键词： Endoscopic retrograde cholangiopancreatography Recurrence Ursodeoxycholic acid Common bile duct stones Clinical effective rate Risk factors

Microscopic Cluster study of the ^(10)Be nucleus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

原子核物理评论 2024年第1期41卷 148-155页

作者： CAO y.ngyu tao Deye ZHOU Bo Institute of Modern Physics Fudan UniversityShanghai 200433China shanghai Research Center for Theoretical nuclear Physics NSFC and Fudan UniversityShanghai 200438China

Using a microscopic four-body cluster model,we investigate the spectral properties and structural configurations of the ^(10)Be *** calculate physical quantities such as the root-mean-squared(r.m.s.)radii and electromagnetic transition *** theoretical results for the energies and certain electromagnetic transition strengths of the low-ly.ng states show good agreement with experimental *** particular,the enhancement of the *** and isoscalar monopole transition strength of the O_(3)^(+) state indicates a well-developed cluster *** obtained three 1-states in E_(x)show remarkable dipole transition strengths,suggesting that the 1-states may have cluster *** the obtained wave functions,we calculate the reduced-width amplitudes(RWAs)to investigate the sHe+α and'Be+n two-body cluster structures in ^(10)*** results suggest that the lowly.ng states show the two-body ^(6)He+α and ^(9)Be+n configuration,with the ^(6)He+α components of the two-body structure diminishing as the energy increases,which due to the breakup of He and ^(9)Be at higher excitation ***,a few states above the α+α+n+n threshold still exhibit significant 9Be+n components.

关键词： cluster model cluster structure electromagnetic transition strengths

The sLEGs beamline of ssRF

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

nuclear science and Techniques 2024年第7期35卷 20-30页

作者： Long-Xiang Liu Hong-Wei Wang Gong-tao Fan Hang-Hua Xu yue Zhang Zi-Rui Hao Ai-Guo Li shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China

The shanghai Laser Electron Gamma source(sLEGs, located in BL03ssID) beamline at the shanghai synchrotron Radiation Facility(ssRF) is a Laser Compton scattering(LCs) gamma source used for the investigation of nuclear structure, which is in extensive demand in fields such as nuclear astrophysics, nuclear cluster structure, polarization physics, and nuclear energy. The beamline is based on the inverse Compton scattering of 10640 nm photons on 3.5 GeV electrons and a gamma source with variable energy by changing the scattering angle from 20° to 160°. γ rays of 0.25-21.1 MeV can be extracted by the scheme consisting of the interaction chamber, coarse collimator, fine collimator, and attenuator. The maximum photon flux for 180° is approximately 10~7 photons/s at the target at 21.7 MeV, with a 3-mm-diameter beam. The beamline was equipped with four types of spectrometers for experiments in( γ,γ'),( γ,n),( γ,p), and( γ,α). At present, nuclear Resonance Fluorescence(nRF) spectrometry, Flat-Efficiency.neutron Detector(FED) spectrometry, neutron Time-Of-Flight(TOF) spectrometry, and Light-Charged Particle(LCP) spectrometry methods have been developed.

关键词： shanghai synchrotron Radiation Facility sLEGs nuclear astrophysics nuclear structure

Interdecadal variability of summer precipitation in the Three River source Region: Influences of ssT and zonal shifts of the East Asian subtropical westerly jet

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic science Letters 2024年第5期17卷 47-53页

作者： yumeng Liu Xianhong Meng Lin Zhao s-y.simon Wang Lixia Zhang Zhaoguo Li Chan Wang y.ngy.ng An Key Laboratory of Cryospheric science and Frozen soil engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina Zoige Plateau Wetlands Ecosystem Research station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina University of Chinese Academy of sciences BeijingChina Utah Climate Center Utah State UniversityLoganUSA The state Key Laboratory of numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina

summer precipitation in the Three Rivers source Region(TRsR)of China is vital for the headwaters of the yellow,y.ngtze,and Lancang rivers and exhibits significant interdecadal *** study investigates the influence of the East Asian westerly jet(EAWJ)on TRsR rainfall.A strong correlation is found between TRsR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,png periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRsR summer *** empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the north Atlantic(nA).The interdecadal variability between the nA and central tropical Pacific(CTP)significantly affects TRsR *** influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°***,the nA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the nA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ.

关键词： summer precipitation East Asian subtropical westerly jet Three River source Region Atlantic-Eurasian teleconnection

synthesis of coral-like structures of Pr-yb co-doped yIG: structural,optical, magnetic and antimicrobial properties

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo y.Guerra s.Castro-Lopes J.Matilla-Arias Idglan s.de Lima Edson C.silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the y_(3-x)Pr_(x)Fe_(5-y)yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. structural investigation certified the yIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of yIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDs) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the yIG structure. A typical ferrimagnetic behavior is exhibited by the y_(3-x)Pr_(x)Fe_(5-y)yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for yIG co-doped with Pr^(3+)and yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against s. aureus, therefore, a new biological property for yIG doped with rare earths is presented.

关键词： yttrium iron garnet(yIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

Geographically and Temporally Weighted Regression in Assessing Dengue Fever spread Factors in y.nnan Border Regions

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental sciences 2024年第5期37卷 511-520页

作者： ZHU Xiao Xiang WAnG song Wang LI y.n Fei ZHAnG ye Wu sU Xue Mei ZHAO Xiao tao national Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases Chinese Center for Disease Control and PreventionBeijing 102211China y.nnan Institute of Parasitic Diseases Pu’er 665000YunnanChina

Objective This study employs the Geographically and Temporally Weighted Regression(GTWR)model to assess the impact of meteorological elements and imported cases on dengue fever outbreaks,emphasizing the spatial-temporal variability of these factors in border *** We conducted a descriptive analysis of dengue fever’s temporal-spatial distribution in y.nnan border *** annual data from 2013 to 2019,with each county in the y.nnan border serving as a spatial unit,we constructed a GTWR model to investigate the determinants of dengue fever and their spatio-temporal heterogeneity in this *** The GTWR model,proving more effective than Ordinary Least squares(OLs)analysis,identified significant spatial and temporal heterogeneity in factors influencing dengue fever’s spread along the y.nnan ***,the GTWR model revealed a substantial variation in the relationship between indigenous dengue fever incidence,meteorological variables,and imported cases across different *** In the y.nnan border areas,local dengue incidence is affected by temperature,humidity,precipitation,wind speed,and imported cases,with these factors’influence exhibiting notable spatial and temporal variation.

关键词： Dengue fever Meteorological factor Geographically and temporally weighted regression