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Phasor-domain Dynamic Model of Asymmetric Current Injection Controller for Converter-interfaced Generator

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1269-1278页

作者： Victor A.f.Almeida Glauco N.Taranto josé M.T.Marinho Electrical Engineering Department of the federal University of Rio de Janeiro(COPPE/UfRJ) Petrobras S.A.

This paper presents a controller model of asymmetric current injection for converter-interfaced generators suitable for root-mean-square(RMS)phasor-domain,fundamentalfrequency,three-phase,and dynamic simulation *** effectiveness of the proposed controller is assessed with simulations in test systems with high percentage of converter-interfaced *** simulations focus on the operation of protection relays that use negative-sequence quantities in their directional *** paper also presents and compares two strategies to limit reactive negative-sequence currents,and active and reactive positive-sequence currents.A tutorial test system and a regional system part of the actual Brazilian Interconnected Power System are used to assess the correctness of the proposed controller in three-phase fundamental-frequency RMS dynamic simulations.

关键词： Converter-interfaced generator three-phase model power system protection negative-sequence current injection negative-sequence current protection unbalanced fault three-phase root-mean-square(RMS)dynamic simulation

Differential response of injured and healthy retinas to syngeneic and allogeneic transplantation of a clonal cell line of immortalized olfactory ensheathing glia:a double-edged sword

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Neural Regeneration Research 2025年第8期20卷 2395-2407页

作者： María Norte-Muñoz María Portela-Lomba Paloma Sobrado-Calvo Diana Simón Johnny Di Pierdomenico Alejandro Gallego-Ortega Mar Pérez joséMCabrera-Maqueda Javier Sierra Manuel Vidal-Sanz María Teresa Moreno-flores Marta Agudo-Barriuso Grupo de Investigación Oftalmología Experimental Departamento de OftalmologíaOptometríaOtorrinolaringología y Anatomía PatológicaFacultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la SaludMurciaSpain Experimental Sciences faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain Anatomy Histology and Neuroscience DepartmentMedicine FacultyUniversidad Autónoma de MadridMadridSpain Center of Neuroimmunology Service of NeurologyLaboratory of Advanced Imaging in Neuroimmunological DiseasesHospital Clínic of BarcelonaInstitut d’Investigacions Biomèdiques August Pi i Sunyer(IDIBAPS)and Universitat de BarcelonaBarcelonaSpain Medicine faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain

Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic ***,it is unknown whether olfactory ensheathing glia also have neuroprotective *** ensheathing glia express brain-derived neurotrophic factor,one of the best neuroprotectants for axotomized retinal ganglion ***,we aimed to investigate the neuroprotective capacity of olfactory ensheating glia after optic nerve *** ensheathing glia cells from an established rat immortalized clonal cell line,TEG3,were intravitreally injected in intact and axotomized retinas in syngeneic and allogeneic mode with or without microglial inhibition or immunosuppressive *** and gene expression analyses were *** bulb-derived primary olfactory ensheathing glia and TEG3 express major histocompatibility complex classⅡ*** and syngenically transplanted TEG3 cells survived in the vitreous for up to 21 days,forming an *** axotomized retinas,only the allogeneic TEG3 transplant rescued retinal ganglion cells at 7 days but not at 21 *** these retinas,microglial anatomical activation was higher than after optic nerve crush *** intact retinas,both transplants activated microglial cells and caused retinal ganglion cell death at 21 days,a loss that was higher after allotransplantation,triggered by pyroptosis and partially rescued by microglial inhibition or ***,neuroprotection of axotomized retinal ganglion cells did not improve with these *** different neuroprotective properties,different toxic effects,and different responses to microglial inhibitory treatments of olfactory ensheathing glia in the retina depending on the type of transplant highlight the importance of thorough preclinical studies to explore these variables.

关键词： cell therapy immune recognition major histocompatibility complex class II(MHCII) neuroprotection olfactory ensheathing glia retinal ganglion cells

Analysis of Viscous Heating in a Micro-Rocket flow and Performance

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Journal of Thermal Science 2008年第2期17卷 116-124页

作者： josé A.Moríigo josé Hermida Quesada Dept.of Space Programmes National Institute for Aerospace Technology Dept.of Aerodynamics and Propulsion National Institute for Aerospace Technology

Micro-rockets for propulsion of small spacecrafts exhibit significant differences with regard to their macroscale counterparts,mainly caused by the role of the viscous dissipation and heat transfer processes in the micron-sized *** goal of this work is to simulate the transient operation of a micro-rocket to investigate the effects of viscous heating on the flow and performance for four configurations of the expanding gas and wafer *** modelling follows a multiphysics approach that solves the fluid and solid regions fully coupled.A contin- uum-based description that incorporates the effects of gas rarefaction through the micro-nozzle,viscous dissipa- tion and heat transfer at the solid-gas interface is ***-equilibrium is addressed with the implementa- tion of a 2nd-order slip-model for the velocity and temperature at the *** results stress that solid-fluid cou- pling exerts a strong influence on the flowfield and performance as well as the effect of the wafer during the first instants of the transient in micro-rockets made of low and high thermal conductivity materials.

关键词： Micronozzles propulsion MEMS slip flow viscous heating

Multiphysics Simulation of a Novel Concept of MEMS-based Solid Propellant Thruster for Space Propulsion

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Journal of Thermal Science 2011年第6期20卷 527-533页

作者： josé A.Moríigo josé Hermida-Quesada Dept.of Space Programmes National Institute for Aerospace Technology Ctra.Ajalvir km.4Torrejón de Ardoz 28850 MadridSpain Propulsion EngineerPh.D. Dept.of Aerodynamics and Propulsion National Institute for Aerospace Technology Ctra.Ajalvir km.4Torrejón de Ardoz 28850 MadridSpain

This work analyzes a novel MEMS-based architecture of submillimeter size thruster for the propulsion of small spacecrafts,addressing its preliminary characterization of *** architecture of microthruster comprises a setup of miniaturized channels surrounding the solid-propellant reservoir filled up with a high-energetic *** channels guide the hot gases from the combustion region towards the nozzle entrance located at the opposite side of the *** simulations of the transient response of the combustion gases and wafer heating in thruster firings have been conducted with fLUENT under a multiphysics modelling that fully couples the gas and solid parts *** approach includes the gas-wafer and gas-polymer thermal exchange,burnback of the polymer with a simplified non-reacting gas pyrolysis model at its front,and a slip-model inside the nozzle portion to incorporate the effect of gas-surface and rarefaction onto the gas ***,accurate characterization of thruster operation requires the inclusion of the receding front of the polymer and heat transfer in the moving gas-solid *** study stresses the improvement attained in thermal management by the inclusion of lateral micro-channels in the *** particular,the temperature maps reveal the significant dependence of the thermal loss on the instantaneous surface of the reservoir wall exposed to the heat flux of hot ***,the simulations stress the benefit of implementing such a pattern of micro-channels connecting the exit of the combustion reservoir with the *** results prove that hot gases flowing along the micro-channels exert a sealing action upon the heat flux at the reservoir wall and partly mitigate the overall thermal loss at the inner-wall vicinity during the *** analysis shows that propellant decomposition rate is accelerated due to surface preheating and it suggests that a delay of the flame extinction into the reservoir

关键词： micronozzles spacecraft micropropulsion solid propellant thrusters

field Efficacy of Chemical Pesticides against Maruca vitrata fabricius(Lepidoptera:Crambidae)Infesting Soybean in Brazil

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American Journal of Plant Sciences 2015年第4期6卷 537-544页

作者： josé fernando Jurca Grigolli André Luis faleiros Lourencao Crébio josé Avila fundação MS Caixa Postal 137 Maracaju Brazil Embrapa Agropecuária Oeste Dourados Brazil

The soybean pod borer, Maruca vitrata, can cause great damage by attacking pods from soybean plants. The aim of this study was to evaluate the field efficacy of chemical pesticides, when applied in spray, against soybean pod borer. The experiment was conducted in the experimental area of fundação, MS, in Maracaju, MS, Brazil, in the growing season 2012/2013. The randomized block design was used with six treatments (teflubenzuron, flubendiamide, methomyl, chlorantraniliprole + lambda-cyhalothrin, chlorpyrifos, and a control treatment without insecticide) and five replications, on cultivar BMX Turbo RR. Evaluations were performed at one, four, seven, 10, and 14 days after pesticides application (DAA), and were based on the percentage of attacked plants with M. vitrata presence, and the number of alive larvae per plant. On each evaluation, 10 plants per plot were analyzed. The data were subjected to ANOVA and the treatment means were compared by Tukey test at 5% probability. Pesticides teflubenzuron, flubendiamide, chlorantraniliprole + lambda-cyhalothrin, and chlorpyrifos significantly reduced the percentage of attacked plants by M. vitrata. Chlorpyrifos, teflubenzuron, and chlorantraniliprole + lambda-cyhalothrin showed higher field efficacy to control M. vitrata from the first day after application. However, flubendiamide showed good efficacy from 10 days after application, and joined the group with higher efficacy (chlorpyrifos, teflubenzuron, and chlorantraniliprole + lambda-cyhalothrin). Methomyl showed no field efficacy against legume pod borer.

关键词： Legume Pod Borer Glycine max Chemical Control

Impact of coronary angioplasty in elderly patients with non-ST-segment elevation myocardial infarction

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Journal of Geriatric Cardiology 2020年第8期17卷 449-454页

作者： fernando f.Goncalves josé P.Guimaraes Sara C.Borges Pedro S.Mateus josé I.Moreira Cardiology Department Centro Hospitalar de Trás-os-Montes e Alto DouroVila RealPortugal

Background As treatment of coronary artery disease improved over the last years,management of elder patients remained a matter of debate since this age group has been underrepresented in most *** study aimed to evaluate a population of patients with≥85 years old with non-ST-segment elevation myocardial infarction(NSTEMI)and compare the prognosis according to coronary revascularization *** We retrospectively studied 324 patients included in a national multicenter registry between October 2010 and October 2018,who underwent coronary angiography and had at least one stenosis≥50%.Results In this population,73.1%of the patients underwent percutaneous coronary intervention(PCI)and 26.9%of the patients underwent optimized medical treatment(OMT).The OMT group had more past history of diabetes,stroke and *** coronary angiography,the PCI group used more often the femoral artery access and single-vessel lesions were also more ***-vessel disease was more common in the OMT *** hospitalization,there were more major bleeding events and death in the PCI *** the one-year follow-up,there were no significant differences in all-cause mortality *** Very old patients with NSTEMI submitted to OMT had more comorbidities and more three-vessel disease,factors that could have influenced the therapeutic *** undergoing PCI had more in-hospital major bleeding events and mortality,with no significant differences after one year.

关键词： Coronary artery disease Revascularization The elderly

Numerical analysis of synthetic granulate deposition in a physical model study

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International Journal of Sediment Research 2014年第1期29卷 110-117页

作者： Gabriele HARB Stefan HAUN joséf SCHNEIDER Nils Reidar B.OLSEN Institute of Hydraulic Engineering and Water Resources Management Graz University of Technology Department of Hydraulic and Environmental Engineering The Norwegian University of Science and Technology

The current study focuses on the application of a three-dimensional numerical model for the prediction of morphological bed *** sediment deposition in a reservoir during a 10-year-fiood was investigated and the results of the simulation were validated with data derived from a physical model *** of the small grain sizes in the prototype,synthetic granulate was used in the physical *** numerical computation domain was a reproduction of the physical model,including the grain sizes and the density of the particles,in order to ensure *** CfD code SSIIM,which solves the RANS-equations in three-dimensions,was used for the *** sediment transport in SSIIM is divided into suspended sediment transport,computed by solving the convection-diffusion equation,and bed-load transport,calculated by an empirical *** results of the numerical simulation correspond well to the results of the physical model *** simulated location and the pattern of the sediment deposition in the reservoir are an accurate representation of the observed distribution in the physical model.

关键词： Physical modeling Numerical modeling RANS-equations Reservoir management Sediment

Slip-model Performance for Underexpanded Micro-scale Rocket Nozzle flows

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Journal of Thermal Science 2007年第3期16卷 223-230页

作者： joséA.Morí■igo joséHermidaQuesada francisco Caballero Requena Dept.of Space Programmes Dept.of

In aerospace Micro-Electro Mechanical Systems （MEMS）, the characteristic length scale of the flow approaches the molecular mean free path, thus invalidating the continuum description and enforcing the use of particle methods, like the Direct Simulation Monte Carlo （DSMC）, to deal with the non-equilibrium regions. Within the slip-regime （0.01〈Kn〈-0.1） both approaches, continuum and particle-based, seem to behave well in terms of accuracy. The present study summarizes the implementation and results obtained with a 2nO-order slip boundary condition in a Navier-Stokes solver to address the rarefaction near the nozzle walls. Its assessment and application to a cold-gas micro-scale conical nozzle of 300μm throat diameter, discharging into the low-pressure freestream, constitutes the major aim of the work. The slip-model incorporates the velocity slip with thermal creep and temperature jump, thus permitting to deal with non-isothermal flows as well. Results show that the gas experiences an intense rarefaction in the lip vicinity, pointing to the limits of model validity. furthermore, a strong Mach deceleration is observed, attributed to the rather thick subsonic boundary layer and supersonic bulk heating caused by the viscous dissipation, in contrast with the expansion to occur in large rocket nozzles during underexpanded operation.

关键词： Slip flow MEMS micronozzles

Multiple primary colorectal cancer: Individual or familial predisposition?

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World Journal of Gastrointestinal Oncology 2015年第12期7卷 434-444页

作者： josé A Pajares josé Perea Department of Gastreoenterology Gregorio Maranon University Hospital Department of Surgery 12 de Octubre University Hospital

Colorectal carcinoma(CRC) is one of the most frequent cancers. Along the surface of the large bowel, several foci of CRC may appear simultaneously or over the time. The development of at least two different tumours has been defined as multiple primary CRC(MPCRC):When more than one tumour is diagnosed at the same time, it is known as synchronous CRC(SCRC), while when a second neoplasm is diagnosed some time after the resection and/or diagnosis of the first lesion, it is called metachronous CRC(MCRC). Multiple issues can promote the development of MPCRC, ranging from different personal factors, such as environmental exposure, to familial predisposition due to hereditary factors. However, most studies do not distinguish this dichotomy. High- and low-pentrance genetic variants are involved in MPCRC. An increased risk for MPCRC has been described in Lynch syndrome, familial adenomatous polyposis, and serrated polyposis. Non-syndromic familial CRCs should also be considered as risk factors for MPCRC. Environmental factors can promote damage to colon mucosae that enable the concurrence of MPCRC. Epigenetics are thought to play a major role in the carcinogenesis of sporadic MPCRC. The methylation state of the DNA depends on multiple environmental factors(e.g., smoking and eating foods cooked at high temperatures), and this can contribute to increasing the MPCRC rate. Certain clinical features may also suggest individual predisposition for MPCRC. Different etiopathogenic factors are suspected to be involved in SCRC and MCRC, and different familial vs individual factors may be implicated. MCRC seems to follow a familial pattern, whereas individual factors are more important in SCRC. further studies must be carried out to know the molecular basis of risks for MPCRC in order to modify, if necessary, its clinical management, especially from a preventive point of view.

关键词： Multiple primary colorectal cancer Synchronous colorectal cancer Metachronous colorectal cancer Chromosomal instability Microsatellite instability CpG island methylator phenotype