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Siderophore-Producing Rhizobacteria as a Promising Tool for Empowering Plants to Cope with Iron Limitation in Saline Soils:A Review

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Pedosphere 2019年第4期29卷 409-420页

作者： maria j.ferreira Helena SILVA Angela CUNHA Biology Department and Centre for Environmental and Marine Studies(CESAM) University of Aveiro Campus de Santigo

Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alternative to chemical fertilizers by simultaneously tackling salt-stress effects and Fe limitation in saline soils. In addition to draught, plants growing in arid soils face two other major challenges: high salinity and Fe deficiency. Salinity attenuates growth, affects plant physiology, and causes nutrient imbalance,which is, in fact, one of the major consequences of saline stress. Iron is a micronutrient essential for plant development, and it is required by several metalloenzymes involved in photosynthesis and respiration. Iron deficiency is associated with chlorosis and low crop productivity. The role of microbial siderophores in Fe supply to plants and the effect of plant growth-promoting rhizobacteria(PGPR) on the mitigation of saline stress in crop culture are well documented. However, the dual effect of siderophore-producing PGPR, both on salt stress and Fe limitation, is still poorly explored. This review provides a critical overview of the combined effects of Fe limitation and soil salinization as challenges to modern agriculture and intends to summarize some indirect evidence that argues in favour of siderophore-producing PGPR as biofertilization agents in salinized soils. Recent developments and future perspectives on the use of PGPR are discussed as clues to sustainable agricultural practices in the context of present and future climate change scenarios.

关键词： aridity bioavailability biofertilizer Fe deficiency high salinity plant growth-promoting rhizobacteria(PGPR) saline stress soil salinization

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The CASTOR-K Code,Recent Developments and Applications

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Plasma Science and Technology 2015年第2期17卷 89-96页

作者： F.NABAIS D.BORBA R.COELHO A.FIGUEIREDO j.ferreira N.LOUREIRO P.RODRIGUES Associao EURATOM/IST Instituto de Plasmas e Fuso Nuclear-Instituto Superior TcnicoUniversidade de Lisboa

The CASTOR-K code is a hybrid magnetohydrodynamic （MHD）-drift kinetic code developed for the study of MHD modes in the presence of energetic ion populations. It allows a fast assessment of the linear stability of the modes, as well as an accurate calculation of damping due to thermal species （Landau damping）. These capabilities make the code an invaluable tool for parametric studies and data analysis. In recent years, CASTOR-K has been mostly used to analyze jET data, including the identification of mechanisms involved in the expulsion of energetic ions from the plasma. However, in order to prepare the code to be used for a wider range of tokamaks including ITER, the code is being subject to a series of important improvements. These improvements aim not only to introduce new physics in the code but also to make it capable of exchanging data with other codes through its integration in modelling infrastructures. In this paper a description of the CASTOR-K code is presented, as well as a summary of the most important results obtained with this code and a description of the new improvements being implemented.

关键词： controlled fusion tokamaks plasma instabilities magnetohydrodynamics(MHD) Alfven waves energetic particles

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Does climate change alter the nutrient trends of Cedrela fissilis *** in the southern Brazilian Amazon?

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Ecological Processes 2023年第1期12卷 806-827页

作者： Daigard R.Ortega Rodriguez Raúl Sánchez-Salguero Andrea Hevia Renata C.Bovi Marciel j.ferreira james H.Speer Fidel A.Roig Mario Tomazello-Filho Escola Superior de Agricultura Luiz de Queiroz Departamento de Ciências FlorestaisUniversidade de São PauloAv.Pádua Dias 11PiracicabaSão Paulo 13418-900Brazil DendrOlavide-Department Sistemas Físicos Químicos y NaturalesUniversidad Pablo de OlavideCrta.Utrera Km.141013 SevilleSpain Department of Ecology Universidad de JaénCampus Las Lagunillas s/n.23009 JaénSpain Departamento de Ciência Florestal Solos e AmbienteUniversidade Estadual PaulistaAv.Universitária 3780BotucatuSão Paulo 18610-034Brazil Laboratory of Silviculture Universidade Federal do Ama-zonasAv.Gen.Rodrigo Octávio 6200ManausAmazonas 69080-900Brazil Department of Earth and Environmental Systems Indiana State UniversityTerre MauteIN 47809USA Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICETUniversidad Nacional de Cuyo)5500 MendozaArgentina Hémera Centro de Observación de la Tierra Escuela de Ingeniería ForestalFacultad de CienciasUniversidad MayorSantiagoChile

Background The increase in the frequency and intensity of droughts is pointed out as one of the main factors altering biogeochemical cycles in the Amazon *** eco-nutritional approach using X-ray fluorescence micro-analysis(μXRF)is proposed to verify the long-and short-term effects of droughts on the growth and xylem nutrient concentrations of Cedrela fissilis *** Fourteen radii were selected from a tree-ring width chronology and X-rayed by Itrax *** of ring width,wood density,and concentrations of aluminum(Al),phosphorus(P),sulfur(S),calcium(Ca),potassium(K),manganese(Mn),iron(Fe)and strontium(Sr)together with Al/Ca,Ca/Mn,K/Ca,Sr/Ca and Mn/S ratios were constructed and correlated with precipitation,temperature,the difference between precipitation and potential evapotranspiration(P-PET)and standardized precipitation-evapotranspiration index(SPEI).Results During dry years,*** showed narrower,less dense rings,lower Al,P,S and Ca,and higher K and Fe concentrations(the opposite was found in wet years).Ring width decreased(together with Al,P,S,K,Ca,Mn,Fe,Sr,Al/Ca,K/Ca and Sr/Ca)and wood density increased(together with Ca/Mn and Mn/S),which was associated with an increase in evapotranspiration and temperature over time,mainly since *** fissilis showed a tendency to increase its capacity for resistance,and a recovery and resilience in growth over time associated with responses in Al,Ca,P and ***,it showed a risk in the capacity for recovery of the pre-drought density values,associated with unsatisfactory responses in Al,Ca,K,Fe and *** This study is the first attempt to analyze tree-ring nutritional evidences of *** trees to climate sensitivity and resilience to drought,based on long-term data from seasonal moist tropical forests of the *** data suggested that *** is undergoing alterations in the concentration,use and redistribution of nutrients associated with increasing wood density and d

关键词： Dendrochemistry μXRF Drought Tropical tree Eco-chemical indicator Resilience Resistance Recovery

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Fluidized and vibrofluidized shallow beds of fresh leaves

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Particuology 2011年第2期9卷 139-147页

作者： Renata de Aquino Brito Lima maria do Carmo ferreira Drying Center of Pastes Suspensions and SeedsChemical Engineering DepartmentFederal University of S o Carlos

The fluid dynamics behavior of shallow fluidized and vibrofluidized beds operating with fresh leaves was investigated with the aim of exploring drying applications in a modified conveyor belt （MCB） system, which may be operated in a fixed- or fluidized-bed mode. Leaves of the specimens Duranta repens, Schinus molle, Coleus barbatus, Buxus sempervirens, and Bougainvillea spectabilis were tested with a range of sphericities from 0.063 to 0.213, bulk densities from 0.038 to 0.251 g/cm3, apparent densities from 0.52 to 0.97 g/cm3 and ratios of total surface area to volume from 21 to 224 cm-1. Fluidization characteristic curves were obtained by measuring pressure drops versus air velocity in a rectangular column of 0.20 m - 0.11 m cross section. It was not possible to reach real fluidized regimes with the leaves due to strongly non-homogeneous beds. Nevertheless, the characteristic curves allowed for the identification of a transition regime from fixed- to expanded-beds, and parameters such as air velocity and pressure drop obtained from the experimental data at the transition were reproducible for specimens with lower surface area or lower specific gravity （i.e., Duranta repens, Schinus molle, and Bougainvillea spectabilis）. The transition velocity and pressure drop could not be predicted by the literature developed for estimat- ing minimum fluidization conditions. The use of vibration at dimensionless vibration parameters （Γ） of 0.5 and 1.0 helped to reduce channeling and decrease the transition velocities from fixed to expanded regimes although it did not affect the pressure drops after the bed expansion. The results suggest that drying fresh leaves using the MCB dryer operating in a fluidized mode would not be feasible because none of the materials investigated attained a high-quality fluidization. Operation of the MCB dryer may be pos- sible by alternating between the fixed and vibrofluidized modes. For the specimens tested, the drying should be performed in a range

关键词： LeavesLow-sphericity particlesPressure dropsFluidizationVibration

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ENERGY ESTIMATES FOR DELAY DIFFUSION-REACTION EQUATIONS

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journal of Computational Mathematics 2008年第4期26卷 536-553页

作者： j.A.ferreira P.M.daSilva CMUC-Departamento Departamento

In this paper we consider nonlinear delay diffusion-reaction equations with initial and Dirichlet boundary conditions. The behaviour and the stability of the solution of such initial boundary value problems （IBVPs） are studied using the energy method. Simple numerical methods are considered for the computation of numerical approximations to the solution of the nonlinear IBVPs. Using the discrete energy method we study the stability and convergence of the numerical approximations. Numerical experiments are carried out to illustrate our theoretical results.

关键词： Delay diffusion reaction equation Energy method Stability Convergence.

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THE EFFECT OF MEMORY TERMS IN DIFFUSION PHENOMENA

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journal of Computational Mathematics 2006年第1期24卷 91-102页

作者： A. Araújo j.A. ferreira P. Oliveira Departamento de Matemática Universidade de Coimbra Portugal

In this paper the effect of integral memory terms in the behavior of diffusion phenomena is studied. The energy functional associated with different models is analyzed and stability inequalities are established. Approximation methods for the computation of the solution of the integro-differential equations are constructed. Numerical results are included.

关键词： Heat propagation Integro-differential equation Numerical approximation,Splitting method

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Drying of pasty and granular materials in mechanically and conventional spouted beds

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Particuology 2019年第1期17卷 176-183页

作者： Robson C. Sousa maria C. ferreira Haritz Altzibar Fábio B. Freire josé T. Freire Rural and Chemical Engineering Department Federal University of Espirito SantoAlegreES. Brazil Chemical Engineering Department Federal University of Sao CarlosSao CarlosSPBrazil Chemical Engineering Department University of Basque CountryBilbaoSpain

A contactor vessel was built to operate as either a mechanically or a conventional spouted bed for the purpose of analyzing the drying of pasty and granular materials under comparable conditions in both configurations. A classical conical–cylindrical spouted bed with a 60° conical base and an air inlet central orifice was modified to enable the switch by introducing in the vessel’s center an open helicoidal conveyor screw placed above the air inlet orifice. This screw is removable and conveniently returns the bed to its conventional spouted configuration. Experiments on drying solutions (calcium carbonate suspensions and skimmed milk) and granular materials (porous alumina particles) were performed for various bed parameter settings. The spouting pressure drop, outlet air temperature, and relative humidity were measured over time under different conditions. Mechanical agitation is proved effective in drying diluted carbonate calcium liquid suspensions and coarse porous alumina particles at an air velocity approximately 50% lower in comparison to drying in a conventional spouted bed. The conventional spouted bed performed better at drying liquid skimmed milk as the mechanical agitation combined with the axial inlet air flow is not effective in mitigating sticking and powder agglomeration in the bed when handling pastes of complex composition. Introducing mechanical agitation in the designed setup broadens the operating range of a conventional spouted bed with axial air flow in the inlet.

关键词： Characteristic curve Drying kinetic Spouted-bed dynamics Mechanical agitation Alumina particles Paste drying

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Investigating the physics of disruptions with real-time tomography at jET

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Plasma Science and Technology 2022年第3期24卷 80-88页

作者： Diogo R ferreira Pedro j CARVALHO Ivo S CARVALHO Chris I STUART Peter j LOMAS jET Contributors 无 Instituto de Plasmas e Fusão Nuclear(IPFN) Instituto Superior Técnico(IST)Universidade de LisboaAv.Rovisco Pais 11049-001 LisboaPortugal Culham Centre for Fusion Energy(CCFE) UK Atomic Energy Authority(UKAEA)Culham Science CentreAbingdonOX143DB OxfordshireUnited Kingdom See the author list of E.joffrin et al 2019 Nucl Fusion 59112021 EUROfusion Consortium JETCulham Science CentreAbingdonOX143DBUK

As jET is developing and testing operational scenarios for higher fusion performance,an increase in pulse disruptivity is being *** a deeper analysis,we find that several radiative phenomena play an active role in determining the outcome of the *** analysis is enabled by the use of real-time tomography based on the bolometer *** though plasma tomography is an inverse problem,we use machine learning to train a forward model that provides the radiation profile directly,based on a single matrix multiplication *** model is used to investigate radiative phenomena including sawtooth crashes,ELMs and MARFE,and their relationship to the radiated power in different regions of *** particular,we use realtime tomography to monitor the core region,and to throw an alarm whenever core radiation exceeds a certain *** results suggest that this measure alone can anticipate a significant fraction of disruptions in the jET baseline scenario.

关键词： plasma tomography machine learning plasma disruptions

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Design and Optimization of a GaN GIT Based PFC Boost Converter

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Chinese journal of Electrical Engineering 2017年第3期3卷 34-43页

作者： Wenbo Wang Frans Pansier jelena Popovic j.A.ferreira Delft University of Technology DelftThe Netherlands

The advent of GaN power devices brings the possibility of pushing up frequencies of power electronics system beyond the capacity of conventional Si *** harvest the high frequency operation benefits of GaN technology,not only GaN devices should be used optimally by providing proper switching and conduction conditions to best accommodate parasitic elements inherent with the devices,other components should also be capable of facilitating high frequency *** this paper,PFC boost converter is used as a platform to harvest the benefits of GaN technology and,at the same time,to uncover the limitations in pushing power electronics systems up.A 600W PFC boost converter with a maximum switching frequency of 3MHz is designed and implemented,which reached an average efficiency of 98.5%.The results indicate that,when properly used,a GaN PFC boost converter could operate at a frequency that is beyond the reach of conventional Si *** well,with availability of GaN devices,high frequency operation of power electronics systems is no longer limited by the lack of switching devices but by practical issues *** frequency magnetic materials,high frequency controllers,etc.

关键词： GaN GIT boost converter PFC high frequency design optimization

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Droplet-based bioprinting enables the fabrication of cell–hydrogel–microfibre composite tissue precursors

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Bio-Design and Manufacturing 2022年第3期5卷 512-528页

作者： Marcin Kotlarz Ana M.ferreira Piergiorgio Gentile Stephen j.Russell Kenneth Dalgarno School of Engineering Newcastle UniversityNewcastle upon Tyne NE17RUUK School of Design University of LeedsLeeds LS29JTUK

Composites offer the option of coupling the individual benefits of their constituents to achieve unique material properties,which can be of extra value in many tissue engineering *** combining hydrogelswith fibre-based scaffolds can create tissue constructs with enhanced biological and structural ***,developing efficient and scalable approaches to manufacture such composites is ***,we use a droplet-based bioprinting system called reactive jet impingement(RejI)to integrate a cell-laden hydrogel with a microfibrous *** system uses microvalves connected to different bioink reservoirs and directed to continuously jet bioink droplets at one another in mid-air,where the droplets react and form a hydrogel that lands on a microfibrous ***–hydrogel–fibre composites are produced by embedding human dermal fibroblasts at two different concentrations(5×10^(6) and 30×10^(6) cells/mL)in a collagen–alginate–fibrin hydrogel matrix and bioprinted onto a fibre-based *** results show that both types of cell–hydrogel–microfibre composite maintain high cell viability and promote cell–cell and cell–biomaterial *** lower fibroblast density triggers cell proliferation,whereas the higher fibroblast density facilitates faster cellular organisation and infiltration into the ***,the fibrous component of the composite is characterised by high swelling properties and the quick release of calcium *** data indicate that the created composite constructs offer an efficient way to create highly functional tissue precursors for laminar tissue engineering,particularly for wound healing and skin tissue engineering applications.

关键词： Bioprinting Hydrogel–fibre composites High-cell-density hydrogels Composite manufacturing

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