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Artificial equilibrium points and bi-impulsive maneuvers to observe 243 Ida

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Chinese Journal of Aeronautics 2021年第1期34卷 410-423页

作者： Allan Kardec de ALMEIDA Jr Geraldo Magela Couto oliveira antonio Fernando Bertachini de Almeida PRADO National Institute for Space Research(INPE) Sao Jose dos Campos 12227-010Brazil Federal Center for Technological Education of Minas Gerais(CEFET-MG) Belo Horizonte 30421-169Brazil

In the restricted three-body problem,the traditional Lagrange points L1 and L2 are the only equilibrium points near the asteroid 243 *** thrust generated by a solar sail over a spacecraft enables the existence of new artificial equilibrium points,which depend on the position of the spacecraft with respect to the asteroid and the attitude of the solar *** equilibrium points generate new spots to observe the body from above or below the plane of *** points are very good observational locations due to their stationary *** work provides a preliminary analysis to observe Ida through the use of artificial equilibrium points as spots combined with transfer maneuvers between *** combination can be used to observe the asteroid from more different points of view in comparison to fixed *** analyses are made for a spacecraft equipped with a solar sail and capable of performing bi-impulsive *** solar radiation pressure is used both to maintain the equilibrium condition and to reduce the costs of the transfers and/or to create transfers with longer *** is a new aspect of the present research,because it combines the continuous thrust with initial and final small impulses,which are feasible for most of the spacecraft,because the magnitudes of the impulses are very *** combined maneuvers may reduce the transfer times of the maneuvers in most of the cases,compared with the maneuvers based only on continuous *** options involved in these transfers are shown,like to minimize the fuel spent(Dv)as a function of the transfer time or to extend the duration of the travel between the *** transfer times can be useful when observations are required during the transfers.

关键词： Artificial equilibrium points Astrodynamics Orbital transfers Solar radiation pressure Solar sail

Selection of Bacillus thuringiensis strains in citrus and their pathogenicity to Diaphorina citri (Hemiptera: Liviidae) nymphs

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Insect Science 2020年第3期27卷 519-530页

作者： Silvia de oliveira Dorta Juliana Balbinotte Rose Monnerat Joao Roberto Spotti Lopes Tatiane da Cunha Odimar Zanuzo Zanardi Marcelo Pedreira de Miranda marcos antonio Machado Juliana de Freitas-Astua Programs de Pos-Graduagao em Microbiologia Agricola Escola Superior de Agricultura Luiz de QueirozUniversidade de Sao PauloPiracicabaSPBrazil Laboratorio de Biotecnologia Centro de Citricultura Sylvio MoreiraInstituto Agronomico de CampinasCordeiropolisSPBrazil Laboratorio de Insetos Vetores de Fitopatdgenos Departamento de Entomologia e AcarologiaEscola Superior de Agricultura Luiz de QueirozUniversidade de Sao PauloPiracicabaSPBrazil Embrapa Recursos Geneticos e Biotecnologia BrasiliaDFBrazil Fundo de defesa da Citricultura(Fundecitrus) AraraquaraSPBrazil Embrapa Mandioca e Fruticultura Cruz das AlmasBABrazil Laboratdrio de Bioquimica Fitopatoldgica Instituto BioldgicoSao PauloSPBrazil

Bacillus thuringiensis(Bt)toxins are effective in controlling insect pests either through the spraying of products or when expressed in transgenic *** discovery of endophytic Bt strains opened new perspectives for studies aimed at the control of sap‐sucking insects,such as the Asian citrus psyllid Diaphorina citri Kuwayama(Hemiptera:Liviidae),a vector of“Candidatus Liberibacter spp.,”associated with citrus huanglongbing(HLB).In this study,translocation of endophytic Bt strains in citrus seedlings inoculated with Bt suspension delivered by soil‐drench,and their systemic pathogenicity to *** nymphs were *** pathogenicity of three wild‐type Bt strains against *** third‐instar nymphs was *** the 10 recombinant strains tested(each of them harboring a single cry or cyt gene),3 can be highlighted,causing 42%–77%and 66%–90%nymphal mortality at 2 and 5 d after inoculation,*** isolation of Bt cells from young citrus shoots and dead nymphs,and PCR performed with specific primers,confirmed the involvement of the Bt strains in the psyllid *** is the first report showing the translocation of Bt strains from citrus seedling roots to shoots and their potential to control *** nymphs that fed on these soil‐drench inoculated *** Bt strains that caused the highest mortality rates have the potential to be used as bioinsecticides to control *** and the identified genes can be used for the production of transgenic Bt citrus.

关键词： Asian citrus psyllid Citrus sinensis Cry toxins endophytic Bt huanglongbing young shoots

Multiple ecological strategies explain the distribution of exotic and native C_(4) grasses in heterogeneous early successional sites in Hawai’i

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Journal of Plant Ecology 2017年第3期10卷 426-439页

作者： Rafael de oliveira Xavier Carla M.D’antonio Ecology and Conservation Lab Department of HydrobiologyFederal University of São CarlosWashington Luís Highwaykm 235São CarlosSão Paulo 13565-905Brazil Environmental Studies Program 4312-L Bren University of CaliforniaSanta BarbaraCA 93106USA

Aims Biotic homogenization results in novel communities contain-ing multiple exotic *** attributes that contribute to the dominance of invaders and increase invasibility of communities have been identified,but rarely have factors governing the domi-nance of co-occurring invaders been *** we assess the presence and performance of five exotic and one native C_(4) grass species across local(microsite)and more broad-scale variation in fire history,soil age,altitude and *** ask whether species show preferences for the same conditions,whether all are constrained by poor soil development,and how their performance changes when alone versus *** addition to providing information useful to managers who want to control some of these species,such information can help to predict how distributions might change with climate change Methods We measured percent cover and plant height of each grass species in 64 plots in each of 15 sites,located in young volcanic substrates across environmental gradients in Hawai’i Volcanoes National Park,Hawai’i,*** varied in fire history and soil age,across altitu-dinal and precipitation *** estimated microsite heteroge-neity by measuring rock cover and soil depth,where each species was present and in plots as a *** analyzed effects of pos-sible controlling variables using chi-square tests and Generalized Additive Mixed *** Findings Two species(Schizachyrium condensatum and Hyparrhenia rufa)were absent in shallow soil,restricted to more mesic sites and showed increasing performance with soil *** contrast,two other species(Andropogon virginicus and Melinis repens)tended to occur in shal-low soil with high rock cover across a wide range of *** addi-tional species(Melinis minutiflora)was weakly affected by soil depth and was the dominant at higher elevation(more mesic)and on burned sites,especially in old *** species was largely absent from lower elevation si

关键词： elevation gradient fire invasive species Melinis minutiflora soil depth

Pathogenesis and clinical management of arboviral diseases

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World Journal of Virology 2025年第1期14卷 9-50页

作者： Victoria Cenci Dietrich Juan marcos Caram Costa Marina Maria Gomes Leite oliveira Carlos Eduardo oliveira Aguiar Luis Guilherme de oliveira Silva Marcel Silva Luz Fabian Fellipe Bueno Lemos Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil

Arboviral diseases are viral infections transmitted to humans through the bites of arthropods,such as mosquitoes,often causing a variety of pathologies associated with high levels of morbidity and *** the past decades,these infections have proven to be a significant challenge to health systems worldwide,particularly following the considerable geographic expansion of the dengue virus(deNV)and its most recent outbreak in Latin America as well as the difficult-tocontrol outbreaks of yellow fever virus(YFV),chikungunya virus(CHIKV),and Zika virus(ZIKV),leaving behind a substantial portion of the population with complications related to these ***,the world is experiencing a period of intense globalization,which,combined with global warming,directly contributes to wider dissemination of arbovirus vectors across the ***,all continents remain on high alert for potential new ***,this review aims to provide a comprehensive understanding of the pathogenesis of the four main arboviruses today(deNV,ZIKV,YFV,and CHIKV)discussing their viral characteristics,immune responses,and mechanisms of viral evasion,as well as important clinical aspects for patient *** includes associated symptoms,laboratory tests,treatments,existing or developing vaccines and the main associated complications,thus integrating a broad historical,scientific and clinical approach.

关键词： Arboviruses Arbovirus infections dengue Zika virus Yellow fever Chikungunya virus Clinical diagnosis Pathogenesis Flavivirus Togaviridae infections

A message classifier based on multinomial Naive Bayes for online social contexts

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Journal of Management Analytics 2018年第3期5卷 213-229页

作者： Thársis Salathiel de Souza Viana marcos de oliveira Ticiana Linhares Coelho da Silva Mário Sérgio Rodrigues Falc ao and Enyo JoséTavares Gonçalves Universidade Federal do CearáQuixadáBrazil

Children and teenagers today are increasingly connected to the *** use by minors of social networks applications,and games that are connected to the internet offer the possibility of communication,can make them exposed to various *** of the most troubling threats is sexual *** the objective of this project is to create a model for classifying messages,as normal or dangerous,according to the risk they present to the *** addition to integrating the developed model with a project that analyzes the behavior of minors in a social network(Facebook),and calculates the risk of the minor be a victim of sexual ***,we use the model in the classification of messages obtained from a server of the game Minecraft,quite popular among children.

关键词： messages exchange classification social media children and teenagers protection minecraft clustering messages

Linking sedimentary provenance,climate and tectonics in the Neoproterozoic SeridóBelt,Borborema Province(NE Brazil)

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Geoscience Frontiers 2023年第6期14卷 414-431页

作者： Carlos V.A.Ribeiro marcos C.C.Sales Armando L.S.de oliveira Ricardo Sallet Programa de Pós-graduação em Geologia Instituto de GeociênciasUniversidade de Brasília(UnB)CEP 70910-900 BrasíliaDFBrazil Programa de Pós-Graduação em Geociências Universidade Federal de PernambucoDepartamento de GeologiaCentro de Tecnologia e GeociênciasAv.da ArquiteturaCEP 50740-530 RecifePEBrazil departamento de Geologia Universidade Federal do Rio Grande do NorteCEP 59078-970 NatalRNBrazil

The SeridóBelt,at the extreme northeast of Brazil,is one of the several Neoproterozoic mobile belts related to the Brasiliano/Pan-African Orogeny in Western *** lithostratigraphy of the SeridóBelt comprises basal quartzites and metaconglomerates(Equador Formation)overlain by hornblende-bearing paragneisses,calc-silicate rocks and marbles(Jucurutu Formation)and biotiteschists(SeridóFormation).We investigated the sedimentary provenance of these rocks based on an integration of compiled whole-rock geochemistry,Sm-Nd isotopes,U-Pb detrital zircon ages and a new set of whole-rock trace elements *** Formation quartzites have major and trace elements patterns that resemble cratonic sandstones,with a typical felsic provenance consistent with the isotopic composition of plutonic Archean to Paleoproterozoic basement *** proxies suggest that these rocks were deposited in fresh waters under anoxic conditions and moderate to intense weathering conditions(CIA=58–79).A shift in provenance led to an increase in intermediate-mafic sources during the deposition of the Jucurutu and Seridó*** elements from rock types in these units are nearly identical,yet they differ on the contents of some high field-strength elements(e.g.,Sc,V and Ni),which are higher in the SeridóFormation than average *** proxies show similar depositional environments,with brackish to marine conditions for the Jucurutu and Seridóformations under anoxic to euxinic *** conditions are consistently lower in the Jucurutu Formation(CIA=58–66)in comparison with the SeridóFormation(CIA=60–88).Compiled U-Pb data suggest maximum depositional ages of 633±11 Ma and 633±6 Ma for Jucurutu and Seridóformations,respectively,suggesting deposition following the ca.645–635 Ma Marinoan *** compared the geochemistry of the SeridóFormation schists with currently exposed basement rocks and showed a strong affinity with Neoproterozoic arc-related

关键词： Whole-rock geochemistry Marinoan Glaciation U-Pb detrital zircon Brasiliano Orogeny

Behavior of wood basic density according to environmental variables

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Journal of Forestry Research 2022年第2期33卷 497-505页

作者： Gabriel marcos Vieira oliveira JoséMárcio de Mello Carlos Rogério de Mello JoséRoberto Soares Scolforo Eder Pereira Miguel Thiago Campos Monteiro Brazil Institute of Agricultural and Forestry defense of Espírito Santo(IDAF) Av.Lourival Lugon Moulinnº300CentroJerônimo MonteiroES CEP:29.550-000Brazil department of Forestry Sciences Universidade Federal de Lavras-UFLACaixa Postal 3037LavrasMG CEP:37.200-000Brazil Engineering department Universidade Federal de Lavras-UFLACaixa Postal 3037LavrasMG CEP:37.200-000Brazil Forestry Engineering department Faculdade de TecnologiaUniversity of Brasilia-UnBCampus Universitário Darcy RibeiroCaixa Postal 4357Asa Norte-BrasíliaDF CEP:70910-900Brazil department of Forestry Engineering and Technology Universidade Federal do Paraná-UFPRAv.Pref.Lothário Meissner632Jardim BotânicoCuritibaPR CEP:80.210-170Brazil

The relationships between climate conditions and wood density in tropical forests are still poorly *** quantify spatial dependence of wood density in the state of Minas Gerais(MG,Brazil),map spatial distribution of density,and correlate density with climate variables,we extracted data from the Forest Inventory of Minas Gerais for 1988 trees scaled throughout the territory and measured wood density of discs removed from the *** variables were extracted from the database of the Ecological-Economic Zoning of Minas *** spatial analysis,tree densities were measured at 44 georeferenced sampling *** data were subjected to exploratory analysis,variography,cross-validation,model selection,and ordinary *** relationships between wood density and environmental variables were calculated using dispersion matrices,linear correlation,and *** density proved to be highly spatially dependent,reaching a correlation of 96%,and was highly continuous over a distance of 228 *** distribution of wood density followed a continuous gradient of 514-659 kg m^(−3),enabling corre-lation with environment *** was correlated with mean annual precipitation(−0.57),temperature(0.63),and evapotranspiration(0.83).Geostatistical methods proved useful in predicting wood density in native tropical forests with different climate *** results confirmed the sensitivity of wood density to climate change,which could affect future carbon stock in forests.

关键词： Biomass Climate variables Geostatistics Hardwood Forest inventory Minas Gerais

Evaluation of the effectiveness of horizontal subsurface flow constructed wetlands for different media

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Journal of Environmental Sciences 2010年第6期22卷 820-825页

作者： antonio Albuquerque José oliveira Sabrina Semitela Leonor Amaral department of Civil Engineering and Architecture and C-MAde University of Beira Interior Municipality of Penamacor department of Sciences and Environmental Engineering Faculty of Sciences and TechnologyNew University of Lisbon

Two media bed （gravel and Filtralite NR） were tested in a mesocosm to evaluate the removal of organic matter （as chemical oxygen demand （COD））, ammonia （NH4-N）, nitrite, nitrate and solid matter （as total suspended solids （TSS）） for a synthetic wastewater （acetate-based） and a domestic wastewater. The use of Filtralite allowed average removal rates （6--16.8 g COD/（m^2·day）, 0.8-1.1 g NH4-N/（m^2·day） and 3.1 g TSS/（m^2·day）） and removal efficiencies （65%-93%, 57%-85% and 78% for COD, NH4-N and TSS, respectively）, higher than that observed in the experiments with gravel. The applied loads of COD, ammonia, nitrate and TSS seem to influence the respective removal rates but only for the treatment of domestic wastewater with nigher correlation coefficients for Filtralite. Regardless the type of media bed and the type of wastewater, nitrate was completely removed for nitrogen loading rates up to 1.3 g NO3-N/（m^2·day）. There was no evidence of the influence of nitrate loads on the removal of organic matter.

关键词： media bed constructed wetlands pollutants removal rates

Computerized geochemical modeling of burial diagenesis of the Eocene turbidite reservoir elements：Urucutuca Formation,Espirito Santo Basin,southeastern Brazil passive margin

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Journal of Palaeogeography 2018年第4期7卷 363-377页

作者： marcos antonio Klunk Sudipta Dasgupta Rommulo Vieira Conceicao Institute of Isotope Geology Federal University of Rio Grande do SulPorto AlegreBrazil department of Earth Sciences Indian Institute of Technology (IIT) BombayMumbai India

The computerized geochemical modeling, a useful tool to understand the diagenetic processes influencing the quality of hydrocarbon reservoirs, is performed by using different modules of computer codes based on the thermodynamic and chemical kinetic principles and their associated parameters. As observed in the reservoir lithofacies deposited from the marine sediment-gravity flows, a case study of diagenesis is presented here from the Espírito Santo Basin in southeastern Brazil. The study uses the Geochemist＇s Workbench（GWB～（TM））, PHREEQC～（TM） and TOUGHREACT～（TM） computation packages. The comparison of performances of these packages demonstrates the convergence of results from the software-based geochemical modeling with the petrographic observation of dissolution, albitization, kaolinization, and the precipitation of calcite and dolomite. Moreover, with limited data points, e.g., the sedimentary petrographic data acquired from limited number of boreholes, the computer simulation establishes itself to be a powerful quantitative method estimating the degree and type of diagenetic alteration of turbidite reservoir bodies in contact with a source of saline-water influx associated with salt ***, using the limited petrographic data points, the geochemical computer-simulation method can even be utilized and extrapolated for areas where similar geological context is interpreted but no borehole data are available. Hence, porosity of turbidite reservoir lithofacies can be predicted in relation to the spatial distribution of dissolution, kaolinization, and albitization of feldspars and authigenic carbonate precipitation.

关键词： Sandstone diagenesis Computerized diagenetic modeling Turbidite reservoir GWB PHREEQC TOUGHREACT