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Soil space and nutrients differentially promote the growth and competitive advantages of two invasive plants

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Journal of Plant Ecology 2014年第4期7卷 396-402页

作者： Yan Gao hong-wei yu wei-Ming He State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesNo.20 NanxincunHaidian DistrictBeijing 100093China University of Chinese Academy of Sciences No.19 Yuquan RoadShijingshan DistrictBeijing 100049China

Aims Invasive plants commonly occupy disturbed soils,thereby provid-ing a stage for understanding the role of disturbance-enhanced resources in plant ***,we addressed how soil space and soil nutrients affect the growth and competitive effect of inva-sive plants and whether this effect varies with different *** We conducted an experiment in which two invasive plants(Bromus tectorum and Centaurea maculosa)and one native species(Poa pratensis)were grown alone or together in four habitats consisting of two levels of soil space and *** the end of the experiment,we determined the total biomass,biomass allocation and relative interaction intensity of ***,*** and *** Findingsacross two invaders,*** and ***,increased soil nutrients had greater positive effects on their growth than increased soil space,the effects of soil space on root weight ratio were greater than those of soil nutrients,and their competitive effect decreased with soil space but increased with soil *** findings sug-gest that changing soil space and nutrients differentially influence the growth and competitive advantages of two *** tectorum benefited more from increased soil resources than *** space and nutrients affected the biomass allocation of *** but not *** competitive effect of ***-rum was unaffected by soil space and soil nutrients,but the opposite was the case for ***,the effects of soil space and nutrients on growth and competitive ability depend on invasive species identity.

关键词： biomass Bromus tectorum Centaurea maculosa competitive ability Poa pratensis soil nutrients soil space

Determining H0 using a model-independent method

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Frontiers of physics 2017年第1期12卷 133-140页

作者： Pu-Xun Wu Zheng-Xiang Li hong-wei yu Center for Nonlinear Science and Department of Physics Ningbo University Ningbo 315211 China Center for High Energy Physics Peking University Beijing 100080 China Department of Astronomy Beijing Normal University Beijing 100875 China

By using type Ia supernovae （SNIa） to provide the luminosity distance （LD） directly, which depends on the value of the Hubble constant H0 = 100h km·s^-1· Mpc^-1, and the angular diameter distance from galaxy clusters or baryon acoustic oscillations （BAOs） to give the derived LD according to the distance duality relation, we propose a model-independent method to determine h from the fact that different observations should give the same LD at a given redshift. Combining the Sloan Digital Sky Survey II （SDSS-II） SNIa from the MLCS2k2 light curve fit and galaxy cluster data, we find that at the 1σ confidence level （CL）, h = 0.5867±0.0303 for the sample of the elliptical β model for galaxy clusters, and h = 0.6199± 0.0293 for that of the spherical β model. The former is smaller than the values from other observations, whereas the latter is consistent with the Planck result at the 2σ CL and agrees very well with the value reconstructed directly from the H（z） data. With the SDSS-II SNIa and BAO measurements, a tighter constraint, h = 0.6683 ± 0.0221, is obtained. For comparison, we also consider the Union 2.1 SNIa from the SALT2 light curve fitting. The results from the Union 2.1 SNIa are slightly larger than those from the SDSS-II SNIa, and the Union 2.1 SNIa ＋ BAOs give the tightest value. We find that the values from SNIa ＋ BAOs are quite consistent with those from the Planck and the BAOs, as well as the local measurement from Cepheids and very-low-redshift SNIa.

关键词： Hubble constant luminosity distance angular diameter distance

The distance duality relation test from the ACT cluster and type Ia supernova data

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Research in Astronomy and Astrophysics 2016年第5期16卷 135-144页

作者： Lin-Hai Hu Pu-Xun Wu hong-wei yu Center of Nonlinear Science and Department of Physics Ningbo University Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University Center for High Energy Physics Peking University

The validity of the cosmic distance-duality （DD） relation is investigated by using 91 measure- ments of the gas mass fraction of galaxy clusters recently reported by the Atacama Cosmology Telescope （ACT） and the luminosity distance from the Union2.1 type Ia supernova （SNIa） sample independent of any cosmological models and the value of the Hubble constant. We consider four different approaches to derive the gas mass function and two different parameterizations of the DD relation, and find that they have very slight influences on the DD relation test and the relation is valid at the la confidence level. We also discuss the constraints on a andβ, which represent the effects of the shapes and colors of the light curves of SNIa, respectively. Our results on a and β are different from those obtained from the ACDM model and the galaxy cluster plus SNIa data.

关键词： cosmology: theory -- galaxies -- clusters: general-distance scale

Roxadustat for treatment of erythropoietin-hyporesponsive anemia in a hemodialysis patient:A case report

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World Journal of Clinical Cases 2020年第23期8卷 6048-6055页

作者： wei-hong yu Xie-Jia Li Fang yuan Department of Nephrology The Second Xiangya Hospital of Central South UniversityChangsha 410011Hunan ProvinceChina

BACKGROUND Hyporesponsiveness to erythropoiesis-stimulating agents(ESAs)is a prevalent problem in patients with chronic kidney *** is associated with increased morbidity and mortality in patients who undergo dialysis.A significant proportion of patients do not respond to iron supplementation and conventional *** report a case of severe ESA hyporesponsiveness-related anemia that was successfully treated with oral *** SUMMARY A 59-year-old Chinese woman had high blood glucose for 25 years,maintenance hemodialysis for 7 years,and recurrent dizziness and fatigue for more than 2 *** tests showed severe anemia(hemoglobin level of 54 g/L),though bone marrow biopsy,fluorescence in situ hybridization,and hemolysis tests were within normal *** initially administered first-line therapies and other adjuvant treatments,such as blood transfusions,ESAs,and adequate dialysis,but the patient did not respond as *** erythropoietinresistant anemia was probably not only due to chronic renal *** patient received the hypoxia-inducible factor prolyl hydroxylase inhibitor roxadustat(100 mg,three times weekly).After 12 wk of treatment,the patient’s hemoglobin increased significantly,and her symptoms were *** the follow-up period,adverse drug reactions were controllable and *** Oral roxadustat is effective and tolerable for the treatment of ESA hyporesponsiveness-related anemia in patients undergoing hemodialysis.

关键词： Renal anemia Erythropoietin hyporesponsiveness Hepcidin Interleukin 6 Roxadustat Case report

Testing the distance-duality relation with data from galaxy clusters and type Ia supernovae

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Research in Astronomy and Astrophysics 2011年第8期11卷 895-901页

作者： Xiang-yun Fu Pu-Xun Wu hong-wei yu Zheng-Xiang Li Institute of Physics Hunan University of Science and Technology Xiangtan 411201 China Center for Nonlinear Science and Department of Physics Ningbo University Ningbo 315211 China Department of Physics and Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal University Changsha 410081 China

We test the distance-duality （DD） relation by combining the angular diameter distance DA provided by two galaxy cluster samples compiled by De Filippis et al. （the elliptical β model） and Bonamente et al. （the spherical β model）, and the luminosity distance DL from Constitution and Union2 type Ia supernova （SNe Ia） datasets. To obtain DL associated with the observed DA at the same redshift, we smooth the noise of the SNe Ia in a model-independent way, obtain the evolutionary curve of DL and, finally, test the DD relation. We find that the elliptical β model, when compared with the SNe Ia from the Constitution compilation, is only consistent with the DD relation at the 3σ confidence level （CL）, while the spherical β model is incompatible with the DD relation at the 3σ CL. For the Union2 compilation, the De Filippis and Bonamente samples are marginally compatible with the validity of the DD relation at the 1σ and 2σ CLs, respectively.

关键词： galaxies: distances and redshifts -- galaxies: clusters: general -- super- novae: general

Aspirin increases susceptibility of Helicobacter pylori to metronidazole by augmenting endocellular concentrations of antimicrobials

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World Journal of Gastroenterology 2009年第8期15卷 919-926页

作者： Xiao-Ping Zhang wei-hong Wang yu Tian Wen Gao Jiang Li Department of Gastroenterology Peking University First Hospital Beijing 100034 China

AIM： To investigate the increasing the susceptibility pylon） to metronidazole. mechanisms of aspirin of Helicobacter pylori （H METHODS： Hpylori reference strain 26695 and two metronidazole-resistant isolates of H pylori were included in this study. Strains were incubated in Brucella broth with or without aspirin （1 mmol/L）. The rdxA gene of Hpylori was amplified by PCR and sequenced. The permeability of Hpylori to antimicrobials was determined by analyzing the endocellular radioactivity of the cells after incubated with [7-^3H]-tetracycline. The outer membrane proteins （OMPs） of Hpylori 26695 were depurated and analyzed by SDS-PAGE. The expression of 5 porins （hopA, hopB, hopC, hopD and hopE） and the putative RND efflux system （hefABC） of H pylori were analyzed using real-time quantitative PCR. RESULTS： The mutations in rdxA gene did not change in metronidazole resistant isolates treated with aspirin. The radioactivity of H pylori increased when treated with aspirin, indicating that aspirin improved the permeability of the outer membrane of H pylori. However, the expression of two OMP bands between 55 kDa and 72 kDa altered in the presence of *** expression of the mRNA of hopA, hopB, hopC, hopD, hopE and herA, hefB, hefC of H pylori did not change when treated with aspirin. CONCLUSION： Although aspirin increases the susceptibility of H pylori to metronidazole, it has no effect on the mutations of rdxA gene of Hpylori. Aspirin increases endocellular concentrations of antimicrobials probably by altering the OMP expression.

关键词： Helicobacter pylori Aspirin Metronidazole Resistance Minimum inhibitory concentrations

Choroid changes in vortex vein-occluded monkeys

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International Journal of Ophthalmology(English edition) 2018年第10期11卷 1588-1593页

作者： Lu-Lu Chen Qiong Wang wei-hong yu You-Xin Chen Department of Ophthalmology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Department of Nephrology Beijing Hospital

AIM：To determine acute and chronic choroidal vascular changes after vortex vein occlusion in ***：One or two temporal vortex veins were occluded in 8 cynomolgus *** angiography（FA）,indocyanine green angiogram（ICGA）,and enhanced-depth imaging optical coherence tomography（EDI-OCT）were performed preoperatively and at 1d,1,4,8 and 12wk after ***-OCT images were binarized to calculate the choroid vascular index（CVI）.RESULTS：ICGA showed delayed filling of choroidal arteries in occluded quadrants in eyes with two occluded temporal vortex veins within *** thickness of the superotemporal choroid increased 1d and 4wk after occlusion,the thickness of the superonasal and inferonasal choroid increased 12wk after occlusion,and the CVI of the superonasal quadrant increased 8wk after occlusion in eyes with 2 occluded vortex veins. CONCLUSION：Occlusion of two vortex veins leads to hemodynamic and structural changes in choroidal layers in the acute phase,while autoregulation may play the main role in the long *** of one vortex vein has little influence on the hemodynamic and structural status of the choroid.

关键词： vortex vein occlusion choroidal circulatory disturbance cynomolgus monkey

Alpha/proton Instability in the Presence of Proton and Alpha Temperature Anisotropy and its Application to the Deceleration of Alpha Particles in the Solar Wind

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Research in Astronomy and Astrophysics 2022年第1期22卷 192-204页

作者： Wen-Lu Zhang Liang Xiang Qiu-Huan Li Si-Yi Lang hong-wei yu Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Institute of Space Physics Luoyang Normal UniversityLuoyang 471934China

Observations of solar wind plasma find that the drift velocity between alpha beams and protons,vα,is reduced with the heliocentric distance,but the ratio of vαto vA(the local Alfven velocity)does not vary obviously and has a typical velocity ratio of vα/vA≤*** alpha beam instability is believed to be responsible for the deceleration of alpha beams in the solar ***,the role of the temperature anisotropy of ions(protons and alpha particles)on the alpha beam instability has not been *** on the kinetic theory of the PDRK solver,this study systemically investigates the alpha beam instability in the presence of proton and alpha temperature anisotropies and considers the effects of these temperature anisotropies on the instability at an arbitrary propagation angle relative to the ambient magnetic *** is found that the real frequencies,growth rates and threshold conditions of the excited waves sensitively depend on the proton temperature anisotropy T_(i⊥)/T_(i‖)and the alpha temperature anisotropy T_(α⊥)/T_(α‖),as well as the parallel electron betaβe‖.In particular,for both alpha beam and proton temperature anisotropy driven cases,the parallel magnetosonic/whistler(PM/W),backward magnetosonic/whistler(BM/W)and oblique Alfvén/ion cyclotron(OA/IC)waves arise when T_(i⊥)/T_(i‖)*** presence of anisotropic protons leads to a lower velocity threshold for the OA/IC and BM/W waves at T_(i⊥)/T_(i‖)*** both alpha beam and alpha temperature anisotropy driven cases,the PM/W and OA/IC waves are unstable when T_(α⊥)/T_(α‖)*** presence of anisotropic alpha particles results in a lower threshold velocity for the PM/W wave at T_(α⊥)/T_(α‖)<1 and for the PA/IC,OM/W and mirror waves at T_

关键词： (Sun:)solar wind Sun:heliosphere waves

Effects of displacement current on wave dispersion relation and polarization properties in auroral plasmas

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Research in Astronomy and Astrophysics 2021年第10期21卷 108-118页

作者： Liang Xiang Bing Ma Qiu-Huan Li Ling Chen hong-wei yu De-Jin Wu Institute of Space Physics Luoyang Nonnal UniversityLuoyang 471934China Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China University of Science and Technology of China Hefei 230026China

In-situ observations from the FREJA magnetospheric research satellite and the Fast Auroral SnapshoT satellite have shown that plasma waves are frequently observed in the auroral plasma,which are believed to be fundamentally important in wave energy dissipation and particle ***,the effects of a displacement current on these waves have not been *** on the two-fluid theory,we investigate the dispersion relation and polarization properties of fast,Alfven,and slow modes in the presence of a displacement current,and the effects of the displacement current on these waves are also *** results show that the wave frequency,polarization,magnetic helicity and other properties for the fast and Alfven modes are highly sensitive to the normalized Alfven velocity v_(A)/c,plasma beta β,and propagation angle θ,while for the slow mode the dependence is *** particular,for both fast and Alfven modes,the magnetic helicity is obviously different with and without the displacement current,especially for the Alfven mode with the helicity reversals from right-handed to left-handed when v_(A)/c increases from 0 to *** charge-neutral condition of both fast and Alfven modes with frequencies larger than the proton cyclotron frequency is invalid in the presence of the displacement ***,the presence of the displacement current leads to relatively large magnetic compressibility for the Alfven mode and relatively large electron compressibility for the fast *** results can be useful for a comprehensive understanding of the wave properties and the physics of particle energization phenomena in auroral plasmas.

关键词： waves magnetohydrodynamics(MHD) planets and satellites:aurorae