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Interaction of Acaena elongata *** Arbuscular mycorrhizal Fungi under Phosphorus Limitation Conditions in a Temperate Forest

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Phyton-International Journal of Experimental Botany 2021年第2期90卷 605-619页

作者： Yasmin vázquez-Santos Yuriana martínez-Orea JavierÁlvarez-Sánchez Noémanuel montaño Sara Lucía Camargo-Ricalde Silvia Castillo-Argüero Departamento de Ecología y Recursos Naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoFacultad de CienciasCiudad de México04510México Departamento de Biología División de Ciencias Biológicas y de la SaludUniversidad Autónoma Metropolitana-IztapalapaCiudad de México09340México

The aim of this study was to analyze the performance of Acaena elongata colonized by arbuscular mycorrhizal fungi(AmF)to different phosphorus(P)concentrations,as a measure of AmF ***,is a species from soils where P availability is limited,such as temperate *** research questions were:1)How do different P concentrations affect the AmF association in Acaena elongata,and 2)How does the AmF association influence ***’s growth under different P concentrations?***’s growth,P content in plant tissue,AmF colonization and dependency were measured under four P concentrations:control(0 g P kg^(-1)),low(0.05 g P kg^(-1)),intermediate(0.2 g P kg^(-1))and high(2 g P kg^(-1))in different harvests.A complete randomized block design was ***’s growth was higher under-AmF in intermediate and high P concentrations,and the lowest growth corresponded to+AmF in the low and intermediate P *** observed a negative effect on the root biomass under+AmF in intermediate P concentration,while the P concentration had a positive effect on the leaf area *** AmF colonization in *** decreased in the highest P concentration and it was favored under intermediate P concentration;while the low and the high concentrations generated a cost-benefit *** results suggest that the performance of some plant species in soils with low P availability may not be favored by their association with AmF,but a synergy between AmF and intermediate P concentrations might drive ***’s growth.

关键词： Abies religiosa forest arbuscular mycorrhizae plant growth soil fertilization

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Takagi-Sugeno Fuzzy Regulator Design for Nonlinear and Unstable Systems Using Negative Absolute Eigenvalue Approach

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 482-493页

作者： Ravi v.Gandhi Dipak m.Adhyaru Department of Electrical Engineering Indian Institute of Technology(IIT)GandhinagarGandhinagar 382355India Department of Instrumentation&Control Engineering Institute of TechnologyNirma UniversityAhmedabad-382481India

This paper introduces a Takagi-Sugeno(T-S)fuzzy regulator design using the negative absolute eigenvalue(NAE)approach for a class of nonlinear and unstable *** open-loop system is initially embodied by the traditional T-S fuzzy model and then,all closed-loop subsystems are combined using the proposed max-min operator in place of traditional weighted average operator from the controller side to lessen the coupling virtually and simplify the proposed regulator *** each virtually decoupled closed-loop subsystem,the composite regulators(i.e.,primary and secondary regulators)are designed by the NAE approach based on the enhanced eigenvalue *** Lyapunov function is utilized to guarantee the asymptotic stability of the overall T-S fuzzy control *** most popular and widely used nonlinear and unstable systems like the electromagnetic levitation system(EmLS)and the inverted cart pendulum(ICP)are simulated for the wide range of the initial conditions and the enormous variation in the *** transient and steady-state performance of the considered systems using the proposed design are analyzed in terms of the decay rate,settling time and integral errors as IAE,ISE,ITAE,and ITSE to validate the effectiveness of the proposed approach compared to the most popular and traditional parallel distributed compensation(PDC)approach.

关键词： Eigenvalue approach nonlinear and unstable systems stability analysis Takagi-Sugeno(T-S)fuzzy regulator

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SCIENTIFIC PRINCIPLES FOR mODIFICATION OF WATER-SOLUBLE POLYmERS. FORmATION OF mACROmOLECULAR COmPLEXES

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Chinese Journal of Polymer Science 1998年第3期16卷 268-278页

作者： PAUTOv v.D. ANUFRIEvA E.v. KRAKOvYAK m.G. Institute of macromolecular Compounds RAS Bolshoy pr. 31 St. Petersburg 199004 RussiaInstitute of Macromolecular Compounds RAS Bolshoy pr. 31 St. Petersburg 199004 RussiaInstitute of Macromolecular Compounds RAS Bolshoy pr. 31 St. Petersburg 199004 Russia

The study of nanosecond dynamics of macromolecules with the lumines-cent methods make it possible to investigate the formation and functioning of polymericcomplexes, polymeric conjugates and macromolecular metal complexes, which are widelyused for solving many practical tasks. The nanosecond dynamics of macromolecules are ahighly sensitive indicator of interpolymer complexes (IPC) formation. It enables us to solvethe problems of studying IPC formation and stability and to investigate the interpolymerreactions of exchange and substitution. The investigation of changes in the rotational mo-bility of globular protein molecules as a whole makes it possible to determine the complexcomposition and its stability, and to control the course of polymer-protein conjugate forma-tion reaction. The nanosecond dynamics of polymers interacting with surfacants' ions (S)are the sensitive indicator of the S-polymer complex formation. A method for determin-ing the equilibrium constants of the S-polymer complex formation was developed on thebasis of the study of polymer chains mobility. It is established that nanosecond dynamicsinfluences the course of chemical reactions in polymer chains. moreover, the marked effectof the nanosecond dynamics is also revealed in the study of photophysical processes (theformation of excimers and energy migration of electron excitation) in polymers with pho-toactive groups. It was found that the efficiency of both processes increases with increasingthe mobility of side chains, the carriers of photoactive groups.

关键词： modification of water-soluble polymers Formation of complexes

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Reporter gene systems for the identification and characterization of cancer stem cells

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World Journal of Stem Cells 2021年第7期13卷 861-876页

作者： NohemíSalinas-Jazmín Arely Rosas-Cruz marco velasco-velázquez Department of Pharmacology School of MedicineUniversidad Nacional Autónoma de MéxicoMexico City 04510Mexico

Cancer stem cells(CSCs)are tumor cells that share functional characteristics with normal and embryonic stem *** have increased tumor-initiating capacity and metastatic potential and lower sensitivity to chemo-and radiotherapy,with important roles in tumor progression and the response to ***,a current goal of cancer research is to eliminate CSCs,necessitating an adequate phenotypic and functional characterization of *** have been developed to identify,enrich,and track CSCs,many of which distinguish CSCs by evaluating the expression of surface markers,the initiation of specific signaling pathways,and the activation of master transcription factors that control stemness in normal *** review and discuss the use of reporter gene systems for identifying *** that are under the control of aldehyde dehydrogenase 1A1,CD133,Notch,Nanog homeobox,Sex-determining region Y-box 2,and POU class 5 homeobox can be used to identify CSCs in many tumor types,track cells in real time,and screen for ***,reporter gene systems,in combination with in vitro and in vivo functional assays,can assess changes in the CSCs *** present relevant examples of these systems in the evaluation of experimental CSCs-targeting therapeutics,demonstrating their value in CSCs research.

关键词： Cancer Gene reporter systems Cancer stem cells Pluripotency transcription factors Anticancer drugs Preclinical analysis Cancer stem cells marker

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Development of mg-Zn-Y-Zr casting magnesium alloy with high thermal conductivity

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Journal of magnesium and Alloys 2021年第5期9卷 1583-1593页

作者： v.E.Bazhenov A.v.Koltygin m.C.Sung S.H.Park Yu.v.Tselovalnik A.A.Stepashkin A.A.Rizhsky m.v.Belov v.D.Belov K.v.malyutin National University of Science and Technology“mISiS” Leninskiy pr.4Moscow 119049 Russia LG Electronics Inc. Yeoui-daeroYeongdeungpo-gu.128LG Twin TowerSeoul 07336 Republic of Korea

magnesium alloys are used in aircraft because of their light ***,for these alloys to be applied in electronic devices,high thermal conductivities are *** high-potential compositions of mg-Zn-Y-Zr alloys were selected by phase composition and their freezing ranges calculated using Thermo-Calc *** alloys were prepared,and their fluidity,hot tearing susceptibility,mechanical properties,and thermal conductivity were obtained and *** alloy composed of mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr was selected for further investigation,because of its high thermal conductivity and satisfactory mechanical *** mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy’s fluidity and hot tearing susceptibility were similar to those of the widespread AZ91 commercial casting magnesium *** influence of a heat treatment regime on the microstructure,thermal conductivity,and mechanical properties of the developed alloy was also *** was established that the room temperature thermal conductivity of the mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy after aging at 300℃for 5 h was 105 W/m K^(-1).Additionally,the following tensile test results were obtained in aged condition:120 mPa yield strength,200 mPa ultimate tensile strength,and 4%*** utilization of solid solution heat treatment at 520℃for 8 h prior to aging can promote up to 9%increase in *** mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr casting alloy can be used as a high thermal conductivity material with industrial applications.

关键词： magnesium alloy mg-Zn-Y-Zr Thermal conductivity Phase composition Fluidity Hot tearing susceptibility

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Influence of oxygen non-stoichiometry on physical properties of NdSr_2mn_2O_(7±δ)

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Journal of Rare Earths 2015年第3期33卷 282-288页

作者： A.m.Yankin A.v.Fetisov O.m.Fedorova S.A.Uporov v.Ya.mitrofanov Laboratory of Static and Kinetics of Processes Institute of Metallurgy of Ural Branсh of Russian Academy of Science Amundsen St. 101 Ekaterinburg 620016 Russia

Nd Sr2mn2O7＋δ compounds were synthesized by ceramic method under three different cooling conditions. The Nd Sr2mn2O7＋δ samples were characterized by powder X-ray diffraction（XRD）. Oxygen non-stoichiometry data for the studied powders were determined by using gravimetric and X-ray photoelectron spectroscopy（XPS） methods. The correlation of cooling method and oxygen as non-stoichiometry was established. The electroconductivity in samples was studied by using four-point probe method, and the strong correlation with non-stoichiometry was found out. magnetization measurements were carried out. It was found that the magnetic and transport properties of the samples were also influenced by oxygen non-stoichiometry. The evolution of the magnetic properties could be explained by the formation of magnetic clusters in the vicinity of oxygen vacancies（Ov） and strong competition between the superexchange and double exchange interactions.

关键词： oxygen stoichiometry gravimetric analysis electroconductivity magnetic properties rare earths

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Emission of high-energy alpha particles in nuclear reactions of ^(48)Ca and ^(56)Fe ions on ^(181)Ta and ^(238)U targets

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Chinese Physics C 2022年第11期46卷 177-194页

作者： Yu.E.Penionzhkevich v.v.Samarin S.m.Lukyanov v.A.maslov m.A.Naumenko Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear ResearchDubna 141980Russia Department of Experimental methods in Nuclear Physics National Research Nuclear UniversityMoscow 115409Russia Department of Nuclear Physics Dubna State UniversityDubna 141982Russia

The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are *** measurements were performed using the high-resolution magnetic analyzer mAvR with beams of ^(48)Ca(280 mev)and ^(56)Fe(320 and 400 mev)on ^(181)Ta and ^(238)U targets at an angle of 0°.A strong dependence of the double differential cross sections for production of alpha particles on the atomic number of the target nucleus was observed,which indicates that fast alpha particles are mainly emitted from the target nucleus;this conclusion was also confirmed by calculations within the time-dependent Schrödinger equation *** analysis of the obtained experimental data was carried out within the model of moving sources modified to consider the kinematic limits for two-body and three-body exit channels.

关键词： alpha particle energy spectra two-and three-body kinematic limits model of moving sources time-dependent Schrodinger equation

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Electrical Properties and Local Domain Structure of LiNbO_3 Thin Film Grown by Ion Beam Sputtering method

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Acta metallurgica Sinica(English Letters) 2013年第5期26卷 630-634页

作者： v.Ievlev v.Shur m.Sumets A.Kostyuchenko voronezh State University Ferroelectric Laboratory IPAm Ural State University voronezh Institute of the State Fire Service of Russian Emergencies ministry

The nanocrystalline ferroelectric LiNbO3 films on（001） Si substrates with the random orientation of polycrystalline grains and the predominance of the grains with lateral orientation of the polar axis were grown using the ion beam sputtering method. The remanent polarization and the coercive field are 12 μC/cm2and 29 kv/cm, respectively. The thermal annealing leads to the coarsening of the grains. The appearance of the ＂local texture,＂ which gives rise to the unipolarity of the heterostructures caused by the predominance of the one direction in the vertical component of the spontaneous polarization, is investigated.

关键词： LiNbO3 thin films Ferroelectrics Domain structure

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Reissner-Nordstrom-de-Sitter-type Solution by a Gauge Theory of Gravity

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Chinese Physics Letters 2008年第10期25卷 3570-3573页

作者： v. Enache Camelia Popa v. Paun m. Agop Department of Theoretical Physics Faculty of Physics Al.I.Cuza University Blvd. Carol No.l 700506 Iasi Romania Department of Physics Faculty of Applied Sciences Politehnica University of Bucharest I 313 Splaiul lndependentei Street 060042 Bucharest Romania Department of Physics Gh. Asachi Technical University Blvd. Mangeron 700029 Iasi Romania Department of Physics University of Athens Athens 15771 Greece

We use the theory based on a gravitational gauge group （Wu＇s model） to obtain a spherical symmetric solution of the field equations for the gravitational potential on a minkowski spacetime. The gauge group, the gauge covariant derivative, the strength tensor of the gauge feld, the gauge invariant Lagrangean with the cosmological constant, the field equations of the gauge potentiaIs with a gravitational energy-momentum tensor as well as with a tensor of the field of a point like source are determined. Finally, a Reissner-Nordstrom-de Sitter-type metric on the gauge group space is obtained.

关键词： WEYL-DIRAC THEORY GRAvITATIONAL-FIELD EQUATIONS INvARIANCE DUALITY gravitational fields DUALITY Gravity Tensor FIELD EQUATIONS gauge theory invariance

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Solid solution strengthening in multicomponent fcc and bcc alloys:Analytical approach

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Progress in Natural Science:materials International 2021年第1期31卷 95-104页

作者： m.Lugovy v.Slyunyayev m.Brodnikovskyy Institute for Problems of materials Science

Based on virtual solvent concept, novel methods are developed to determine interatomic distance, atomic size misfit, and elastic modulus misfit in multicomponent alloys with components having the crystal structure differing from that of the alloy. The combination of the different methods results in a number of models to calculate solid solution strengthening. These models are assessed with view point of the best fit to experimental data. The models giving the most reliable strengthening prediction can be used for an evolutionary design of strong and stable multicomponent alloys.

关键词： multicomponent alloy Solid solution strengthening model Atomic size misfit Elastic modulus misfit

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