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A Study of the Magnetospheric Micropulsations Pc5 and Pc6 Using Magnetic Stations at Low Latitude Northern Region of Brazil and Ascension Island during Magnetic Stormed Magnetospheric Plasma

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Journal of Electromagnetic Analysis and Applications 2019年第4期11卷 41-54页

作者： Vinícius José Oliveira Werneck de Carvalho Luiz Carlos de Carvalho Benyosef altair souza de assis departamento de Geofísica Observatório Nacional Rio de Janeiro Brazil departamento de Matemática Aplicada Universidade Federal Fluminense Niterói Brazil

In general, micropulsation is generated by the free energy within the magnetosphere, which is mainly caused by the magnetosphere-solar wind interactions and/or magnetic field reconnections in the magnetospheric tail. In this article, we studied the types of low-frequency magnetospheric micropulsations Pc5 and Pc6 (1 - 6 mHz), during three magnetic storms, using ground magnetic observations. One of the main motivations of this study was to produce scientific knowledge on the subject in order to fill knowledge gaps in this region, collaborating with existing bibliographies. The data were recorded in a series of six Brazilian stations close to the Dip Equator (dip = 0), with using data from the Ascension Island observatory. Pulse trains were found to occur simultaneously with almost identical waveforms, with significant amplitude increase near magnetic local noon. Amplitude spectra showed a clear similarity in all equatorial seasons. The results obtained were compared with studies performed in regions with similar low latitudes. The possible mechanisms that induced these micropulsations and the peculiarities presented by these data were also discussed in this article.

关键词： Magnetospheric Micropulsations Electrojet Equatorial Alfvén Waves Geomagnetic Storms

Growth and nutrient accumulation of Brazil nut trees(Bertholletia excelsa) in agroforestry at different fertilizer levels

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Journal of Forestry Research 2015年第2期26卷 347-353页

作者： Gotz Schroth Maria do Socorro souza da Mota Maria Elizabeth de assis Elias C.P. 513 Santarem PA 68109-971 Brazil Centro de Estudos Avanqados de Promoqao Social e Ambiental Av. Mendonqa Furtado 3979 Santarem PA 68040-050 Brazil Universidade Federal do Amazonas Manaus AM 69077-000Brazil

The Brazil nut tree（Bertholletia excelsa） is a frequent component of agroforestry systems in the Amazon because of its adaptation to nutrient-poor upland soils and multiple *** investigated the aboveground biomass production（kg dry weight）,nutrient uptake and requirements（N,P,Ca,Mg,K） of Brazil nut trees of different sizes grown under agroforestry conditions and fertilized at different *** of 70 experimental trees with different size were harvested and stem,branches and leaves were *** contents were determined for three trees of varying *** tree growth was fast,but variability was high,suggesting considerable potential for the improvement of this economically important *** trees responded to increased levels of fertilizer and lime with significantly increased foliar nutrient contents and growth,probably because of the improved availability of Mg and Ca for which the species seems to have a relatively high *** contrast to Brazil nut trees grown in forest or dense plantations,the agroforestry trees invested a substantial part of their biomass and nutrients in large branches and developed spreading *** improve stem form,reduce competition with associated crops for light and recycle nutrients,regular pruning of lower branches or planting arrangements that favor self-pruning are *** measures would also increase the recycling of Ca and Mg,large quantities of which are contained in the branches.

关键词： Allometric equation Amazon Nutrient competition Nutrient recycling Plant mineral nutrition Soil fertility Silviculture

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Petrogenesis of Granites from the Ediacaran Socorro Batholith,SE Brazil:Constraints from Zircon Dating,Geochemistry and Sr-Nd-Hf Isotopes

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Journal of Earth Science 2021年第6期32卷 1397-1414页

作者： Bárbara Bueno Toledo Valdecir de assis Janasi Instituto de Geociências USPCEP 05508-900S∼ao PauloSPBrazil

Whole rock elemental and Sr-Nd isotope geochemistry and in situ zircon Hf isotope geochemistry were used to identify the sources of the Neoproterozoic granites from the Socorro batholith,Socorro-GuaxupéNappe(SGN),South Brasilia Orogen,*** trace elements and Hf isotope geochemistry provided information about sources and crystallization(T,f_(O2))*** main types of granites built the bulk of the batholiths,beginning with probably pre-collisional~640–630 Ma charnockites,and ending with~610 Ma voluminous post-collisional high-K calc-alkaline(HKCA)Ⅰ-type granites(Bragan?a Paulista-type).Several types of leucogranites were generated from 625 to 610 Ma,spanning the interval from collisional to post-collisional *** charnockite bodies occur in the study area:the~640 Ma Socorro charnockite has remarkable chemical similarities with Braganca Paulista-type granites,but higherε_(Nd)(t)=-6.1 and average zirconε_(Hf)(t)=-9.1 and lower^(86)Sr/^(87)Sr_(t)(0.7093)values,indicative of more juvenile and water-poor ***~633 Ma Atibaia charnockite has distinct geochemical signature(lower Mg^(#)and Sr content;higher Zr),more negativeε_(Nd)(t)=-14.1,similar average zirconε_(Hf)(t)=-8.9,and much higher^(86)Sr/^(87)Sr_(t)=0.7197,probably reflecting a larger component from old *** predominant~610 Ma Bragan?a Paulista-type granites were emplaced in a post-collisional setting,and correspond to porphyritic biotite-hornblende monzogranites of high-K calc-alkaline character with 61 wt.%–67 wt.%SiO_(2),high Mg^(#)(39–42),Sr/Y(19–40),La/Yb(12–69),highly negativeε_(Nd)(t)(-12.3 to-12.9)and zirconε_(Hf)(t)(-12 to-17)and^(87)Sr/^(86)Sr_(t)=0.7119–*** features are interpreted as indicative of magma generation in a thickened crust,where melts from enriched mantle sources emplaced in the lowermost crust,heated host old continental crust rocks(gneisses and granulites)and partially mixed with their melting *** plutons(SiO_(2)>72 wt.%)occur

关键词： U-Pb dating Socorro-GuaxupéNappe high-K calc-alkaline granites

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Apparent soil electrical conductivity in the delineation of management zones for cocoa cultivation

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Information Processing in Agriculture 2022年第3期9卷 443-455页

作者： Samuel de assis Silva Railton Oliveira dos Santos Daniel Marcal de Queiroz Juliao Soares de souza Lima Levi Fraga Pajehua Caique Carvalho Medauar Center for Agricultural Sciences and Engineering Federal University of Espirito SantoAlegre CampusEspirito Santo 29500-000Brazil department of Agricultural Sciences Santa Cruz State UniversityIlheusBahia 45662-900Brazil department of Agricultural Engineering Federal University of Vic¸osaVic¸osaMinas Gerais 36570-900Brazil

Apparent electrical conductivity is an important parameter for describing the spatial vari-ability of physical and chemical attributes of the soil and for the delineation of manage-ment *** objective of this work is to outline management zones for the cocoa cultivation based on the spatial variability of the productivity and the apparent electrical conductivity(ECa)of the *** collection was performed in a regular sample grid con-taining 120 points in an area cultivated with cocoa trees,located in the municipality of Ilhe´us,state of Bahia,*** each sampling point(cocoa tree),soil samples were col-lected to determine chemical *** was measured for one year,counting,monthly,the number of fruits,which were classified into off-season cocoa,harvest and annual *** of the apparent electrical conductivity of the soil were performed at different times of the year using a portable conductivity *** data were analyzed using classical statistics and *** management zones were delin-eated using the fuzzy k-means *** ideal number of class was defined using the fuzziness performance index(FPI)and the entropy of the modified partition(MPE)*** Kappa coefficient was used to validate the management zones,assessing their agreement with the chemical attributes of the *** ECa of the soil values pre-sented moderate temporal variation,with maximum amplitude of 19.37 mS m1 and min-imum of 0.82 mS m1 between measurement periods;higher averages of the ECa coincided with the highest levels of water in the *** measurements of the ECa of the soil carried out in April and October showed greater correlation with the chemical attributes of the soil,with significant values for 11 and 8 of the 17 attributes evaluated,*** man-agement zones from the ECa measured in April showed:a)reduced number of classes;b)spatial continuity between classes,and;c)agreement from reasonable(kappa between

关键词： Theobroma cacao Precision agriculture Spatial variability Fuzzy k-means

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The AK Transform

Applied Mathematics 2017年第2期8卷 145-153页

作者： altair S. de assis Siegbert Kuhn Juan A. Limaco Comiss&atilde o Nacional de Energia Nuclear—DPD Rio de Janeiro RJ Brasil Universidade Federal Fluminense—GMA Niterói RJ Brasil Universitä t Innsbruck Institut für Theoretische Physik Innsbruck Austria

In this brief communication we present a new integral transform, so far unknown, which is applicable, for instance, to studying the kinetic theory of natural eigenmodes or transport excited in plasmas with bounded distribution functions such as in Q machines/plasma diodes or in the scrap-off layer of Tokamak fusion plasmas. The results are valid for functions of function spaces—Lebesgue spaces, which are defined using a natural generalization of the p-norm for finite-dimensional vector spaces, where is the real set, σs is the σ-algebra of Lebesgue measurable sets, and the μ Lebesgue measure. , so that . Note that, using a simpler notation, more natural/known to engineers, f could be considered any piecewise continuous function, that is: Here is a Euclidian space with the usual norm (inner product: ) given by: [1].

关键词： Integral Transform Lebesgue Measures Kinetic Theory of Bounded Plasmas Natural Eigenmodes Transport Q-Machines Plasma Diodes Tokamak Nuclear Fusion

Structure and genetic diversity of natural populations of Guadua weberbaueri in the southwestern Amazon,Brazil

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Journal of Forestry Research 2021年第2期32卷 755-763页

作者： Glória da Silva Almeida Leal Fabrício assis Leal Hugo Teixeira Gomes Anderson Marcos de souza Sabina Cerruto Ribeiro Jonny Everson Scherwinski-Pereira Centro Multidisciplinar Universidade Federal do AcreCruzeiro do SulAcreBrazil Universidade de Brasília BrasíliaDistrito FederalBrazil Centro de Ciências Biológicas e da Natureza Universidade Federal do AcreRio BrancoAcreBrazil Centro de Pesquisa e Aplicação de Bambu e Fibras Naturais Universidade de Brasília–CPAB/UnBBrasíliaDistrito FederalBrazil Embrapa Recursos Genéticos e Biotecnologia Av.W5 Norte(final)PqEBBrasíliaDistrito Federal 70770-917Brazil

The Brazilian state of Acre has an extensive natural reserve of bamboo,making it one of the largest in loco gene *** aim of this study was to characterize the structure and genetic diversity of Guadua weberbaueri *** two populations,one native(FAPB)and the other anthropized(FAPBA),using ISSR *** results show that the FAPB population exhibited higher values for all estimates of population ***,the FAPBA population also showed high heterozygosity,corroborated by estimated gene flow(Nm=3.9)between the *** study of the association between Nei’s genetic distances and the geographic distances between the populations were significantly correlated(r=0.45,p=0.01),corroborated by the dendrogram revealing two distinct groups corresponding to the collection sites,without mixing classes between populations in the same *** for the coancestry coefficient,pairs of individuals in the first distance class were positive and significant,indicating that plants that are geographically closer share common alleles with a frequency greater than by chance,which means that there is a tendency that geographically closer individuals are *** presented similar genetic structure when the geographical distance between them was up to 56 m for FAPB and up to 156 m for *** was concluded that anthropized environments exhibit less genetic diversity than native environments,inferring risks for species conservation if appropriate and planned management techniques are not adopted.

关键词： Guadua Bamboo Genetic diversity Amazon rainforest Anthropized and native populations Underutilization plants

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Can the Glucose Central Control System Dysfunctions Induce Diabetes Mellitus?

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Open Journal of Endocrine and Metabolic Diseases 2023年第12期13卷 244-255页

作者： altair S. de assis João Luiz P. da Nobrega Cooperation Center for the development of Children and Adolescents—CCDIA Niterói RJ Brasil

We study afresh how the glucose control system anomalies impact the organicity of the glucose homeostasis and build up events of persistent hyperglycemia and diabetes mellitus. We have used critically the state of art literature related to the subject, in order to cross, to compare, and to organize the relevant contents to create a logical and consistent support to the finds. We show that it is consistent to assume that persistent hyperglycemia and diabetes mellitus can have precursors not only in pancreas, but also in brain, mainly induced by noxious dysfunctions of hypothalamus sensor neurons circuits and external noxious elements, causing pancreas overload, and the consequent exhaustion—overburden.

关键词： Brain Hypothalamus CNS—Central Nervous System Sensor Neuron Circuits Glucose Central Control System External Noxious Elements Juvenile Persistent Hyperglycemia Diabetes Mellitus Homeostasis Euglycemia

Convective Schrodinger Equation:Insights on the Potential Energy’s Role to Wave Particle decay

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Journal of Electromagnetic Analysis and Applications 2015年第9期7卷 225-232页

作者： altair S.de assis Hector Torres-Silva Goran T.Marklund Universidade Federal Fluminense(IM-GMA) NiteroiBrasil Universidad de Tarapaca AricaChile Kungliga Tekniska Hogskolan—KTH StockholmSweden

In this paper, we coupled the Quantum Mechanics conventional Schrödinger’s equation, for the particles, with the Maxwell’s wave equation, in order to study the potential’s role on the conversion of the electromagnetic field energy to mass and vice versa. We show that the dissipation (“conductivity”) factor and the particle implicit proper frequency are both related to the potential energy. We have also derived a new expression for the Schrödinger’s Equation considering the potential energy into this equation not as an ad hoc term, but also as an operator (Hermitian), which has the scalar potential energy as a natural eigenvalue of this operator.

关键词： Schrodinger’s Equation Klein-Gordon’s Equation Maxwell’s Wave Equation Convection Displacement Current

Impacts of land use and land cover changes on hydrological processes and sediment yield determined using the SWAT model

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International Journal of Sediment Research 2022年第1期37卷 54-69页

作者： Edivaldo Afonso de Oliveira Serr?o Madson Tavares Silva Thomás Rocha Ferreira Lorena Concei??o Paiva de Ataide Cleber assis dos Santos Aline Maria Meiguins de Lima Vicente de Paulo Rodrigues da Silva Francisco de assis Salviano de Sousa denis José Cardoso Gomes Academic Unit of Atmospheric Sciences Federal University of Campina Grande department of Physics Center for Natural and Exact Sciences Federal University of Santa Maria Institute of Technology Civil Engineering Graduate Program Federal University of Pará Earth System Science Center National Institute of Space Research Institute of Geosciences Federal University of Pará

Land use and land cover (LULC) changes strongly affect local hydrology and sediment *** current study focused on a basin in the Brazilian Amazon and had the following three objectives:(1) to perform an effective diagnosis of flow and sediment yield,(2) to evaluate the impacts of LULC changes over the last 40 years on the hydro-sedimentological variables,and (3) to investigate the impacts of the possible trends or breaking points in the flow,surface runoff,and sediment yield *** Soil and Water Assessment Tool (SWAT) model validation showed that the simulated results were consistent with the data measured in the dynamic reproduction of flow ***,changes in LULC altered surface runoff,sediment yield,and flow according to the Mann-Kendall and Pettitt non-parametric *** was also observed that the sub-basins in which pastureland is predominant are more susceptible to increased surface runoff and sediment *** to trend and homogeneity tests,these sub-basins had break points in the time series of these *** the other hand,in the sub-basins whose land cover is predominantly forest,the time series is homogeneous and *** current study highlighted the impacts that 40 years of LULC changes in an Amazonian basin had on hydro-sedimentological variables,which,in turn,can play an important role in changing the hydrological cycle,consequently these changes can also impact diverse human activities in the region,such as agribusiness,livestock,energy production,food security,and public water ***,it is concluded that the SWAT model is a good estimator of hydro-sedimentological processes in Amazonian basins and can be used by decision makers in the management of water and environmental resources.

关键词： Hydrological modeling Sediment yield Amazon basin SWAT model