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Droughts in the Amazon: Identification, Characterization and Dynamical Mechanisms Associated

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American Journal of Climate Change 2017年第2期6卷 425-442页

作者： sérgio Rodrigo Quadros dos sant.s Célia Campos Braga Clovis Angeli sansigolo T. T. de Araujo Tiburtino Neves Ana Paula Paes dos sant.s National Institute for space Research (INPE) S&atilde o José dos Campos SP Brazil Federal University of Campina Grande (UFCG) Campina Grande PB Brazil Federal University of Pará Western Brazil (UFOPA) Santarém Pa Brazil

In this study, we used the standard Precipitation Index (sPI) to identify and to characterize the dry extreme events in the Amazon region. The results showed that the drought of 1998 was the most intense (sPI average equal to -1.69) in the period from 1979 to 2014. However, some papers have characterized the years 2005 and 2010 as the two largest droughts of the century. Thus, it was also carried out a comparative study of these droughts. The results showed that the drought 1998 was more intensive and extreme than the droughts of 2005 and 2010, although droughts of 2005 and 2010 lasted longer than 1998 due to oceanic and atmospheric conditions with influencing to cause greater social and economic impacts. Furthermore, it is suggested that the impact of the 2005 and 2010 droughts is a response from the dry occurred in 1993-1994 and 1997-1998.

关键词： Precipitation Extremes Dry Rainy sPI Amazonia

Water availability drives gradients of tree diversity,structure and functional traits in the Atlantic-Cerrado-Caatinga transition,Brazil

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Journal of Plant Ecology 2018年第6期11卷 803-814页

作者： Marcela de Castro Nunes sant.s Terra Rubens Manoel dos sant.s Jamir Afonso do Prado Júnior José Marcio de Mello José Roberto soares scolforo Marco Aurélio Leite Fontes Ivan schiavini Aliny Aparecida dos Reis Inacio Thomaz Bueno Luiz Fernando silva Magnago Hans ter steege Departamento de Ciências Florestais Universidade Federal de LavrasCampus UniversitárioPO Box 3037LavrasMinas Gerais 37200-000Brazil Instituto de Biologia Universidade Federal de UberlândiaCampus Umuarama-Bloco 2DPO Box 593UberlândiaMinas Gerais 38400-902Brazil Applied Ecology and Conservation Lab Programa de Pós‐graduação Ecologia e Conservação da BiodiversidadeUniversidade Estadual de Santa CruzIlhéusBahia 45662-900Brazil Naturalis Biodiversity Center Vondellaan 55Postbus 95172300 RA LeidenThe Netherlands Coordenação de Botânica Museu Paraense Emílio GoeldiAv.Magalhães Barata 376PO Box 399BelémPara´66040-170Brazil

Aims Climate and soil are among the most important factors determin-ing variation in tree communities,but their effects have not been thoroughly elucidated to date for many vegetation *** this study,we evaluate how climate and soil gradients affect gradients of vegetation composition,species diversity and dominance,structure and functional traits(seed mass and wood density)using over 327000 trees in 158 sites distributed along environmental gradients in the transitions among the Atlantic forest,Cerrado and Caatinga in Minas Gerais state(MG),Brazil(nearly 600000 km2).Methods Gradients in species,genus and family abundance in addition to basal area,stem density,species diversity(Fisher’s alpha),domin-ance percentage,seed mass and wood density were correlated using multiple regressions with environmental variables,as summarized in four principal component analysis axes(two climatic-precipi-tation seasonality and temperature range-and two edaphic-soil fertility and soil moisture).Additionally,ordinary kriging maps were used to better illustrate the *** Findings Multiple regression models indicate that all variables but domin-ance percentage were affected by one or more of the environmental gradients,but the average R2 was low(26.25%).Kriging maps rein-forced the patterns observed in the regression *** seasonality and soil moisture gradients were the most important gra-dients affecting vegetation *** finding suggests that water availability is an important determinant of vegetation features in these vegetation transitions.

关键词： climate environmental gradient soil southeastern Brazil vegetation

Design of N-11-Azaartemisinins Potentially Active against Plasmodium falciparum by Combined Molecular Electrostatic Potential, Ligand-Receptor Interaction and Models Built with supervised Machine Learning Methods

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Journal of Biophysical Chemistry 2023年第1期14卷 1-29页

作者： Jeferson stiver Oliveira de Castro José Ciríaco Pinheiro sílvia simone dos sant.s de Morais Heriberto Rodrigues Bitencourt Antonio Florêncio de Figueiredo Marcos Antonio Barros dos sant.s Fábio dos sant.s Gil Ana Cecília Barbosa Pinheiro Instituto de Educação Ciência e Tecnologia do Pará Castanhal PA Brasil Laboratório de Química Teórica e Computacional Universidade Federal do Pará Belém PA Brasil Instituto Amazônia dos saberes São Luís MA Brasil Universidade do Estado do Amapá Macapá AP Brasil Laboratório de síntese Universidade Federal do Pará Belém PA Brasil Universidade do Estado do Pará Belém PA Brasil Fundação santa Casa de Misericórdia do Pará Belém PA Brasil

N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning methods (PCA, HCA, KNN, sIMCA, and sDA). The optimization of molecular structures was performed using the B3LYP/6-31G* approach. MEP maps and ligand-receptor interactions were used to investigate key structural features required for biological activities and likely interactions between N-11-azaartemisinins and heme, respectively. The supervised machine learning methods allowed the separation of the investigated compounds into two classes: cha and cla, with the properties εsub>LUMO+1sub> (one level above lowest unoccupied molecular orbital energy), d(Csub>6sub>-Csub>5sub>) (distance between Csub>6sub> and Csub>5sub> atoms in ligands), and TsA (total surface area) responsible for the classification. The insights extracted from the investigation developed and the chemical intuition enabled the design of sixteen new N-11-azaartemisinins (prediction set), moreover, models built with supervised machine learning methods were applied to this prediction set. The result of this application showed twelve new promising N-11-azaartemisinins for synthesis and biological evaluation.

关键词： Antimalarial Design MEP Ligand-Receptor Interaction supervised Machine Learning Methods Models Built with supervised Machine Learning Methods

Hydrogeochemical Research of surface Water of the Córrego sujo Watershed, Teresópolis, RJ, Brazil

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Agricultural sciences 2017年第5期8卷 435-450页

作者： Paula Coelho Araujo André s. Avelar Vítor dos sant.s Costa Maria Isabel Martinez Geoscience Department Federal University of Rio de Janeiro Rio de Janeiro Brazil

The surface water quality was investigated in the Córrego sujo watershed, located in the municipality of Teresópolis, a mountainous region in the state of Rio de Janeiro, Brazil. The emphasis focused on inorganic parameters of water, since there are applications of pesticides in agricultural cultivations. The natural and anthropogenic contributions of the study area were monitored monthly in eight sites in the river channels of the drainage basin. The results were analyzed using an ICP-OEs spectrophotometer and subsequently compared to Conama Resolution 357/05. In order to support the interpretation of the results of water quality, flow and precipitation data were measured in the watershed, along with the land use and vegetation cover map produced from a GeoEye satellite image. The study revealed that the surface waters were in high concentrations and above those recommended by Conama Resolution. It was noted also that the lithological and pedological variables influenced the results of water quality. Regarding seasonality, it has not been possible to establish a common standard to all elements in the rainy season or dry season, however, in the analysis of each parameter separately, there was evidence of a concentration distribution in temporal variation. Therefore, the results of this study indicate that it is also necessary to highlight these issues in the territorial planning of the municipality and in the management of the Committee of Rio Piabanha watershed, to avoid the increasing of uncontrolled expansion of irrigated crops and intensive use of agrochemical inputs.

关键词： Hydrogeochemistry Natural and Anthropogenic Influences Land Use surface Waters Rivers

GPR Tomographic Imaging of Concrete Tubes and steel/Plastic Tanks Buried in IAG/UsP Geophysical Test site, Brazil

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International Journal of Geosciences 2017年第5期8卷 647-658页

作者： Jorge Luís Porsani Emerson Rodrigo Almeida Bruno Poluha Vinícius Rafael Neris dos sant.s Universidade de sã o Paulo Instituto de Astronomia Geofísica e Ci&ecirc ncias Atmosféricas Departamento de Geofísica. Rua do Mat&atilde o 1226 Butant&atilde S&atilde o Paulo Brazil

In this paper, the Ground Penetrating Radar (GPR) method was used to characterize concrete tubes and steel/plastic tanks buried in IAG/UsP test site. The microwave tomography was used to improve the GPR images, aiming to retrieve the geometry of the targets. The numerical modeling studies also were done in order to predict the GPR results of the buried targets and to give more reliability to the results interpretation. The targets were installed in the first shallow geophysical test site of the Brazil located at Institute of Astronomy, Geophysics, and Atmospheric science (IAG) of the University of s?o Paulo (UsP). GPR profiles of 200 MHz (shielded bistatic antennas) were acquired along three lines containing concrete tubes and steel/plastic tanks buried in subsoil. The concrete tubes show a hyperbolic reflector for the top, and the vertical tube also presented a reflection on its bottom. The horizontal steel tanks were characterized by a strong GPR reflection on their top. The empty plastic tank shows a strong reflector for the top with normal polarity. On the other hand, the plastic tank filled with water shows a weaker reflector for its top characterized by the inverted polarity of GPR signal when compared with empty plastic tank. The plastic tank filled with water also went characterized by the strong reflection to its bottom, being a good indicative to interpret GPR data on target in subsoil with some types of fluid inside of tank. The results of polarity difference for the top of tank can be used as guide pattern to identify buried tank empty or filled with water. The application of microwave tomography to the GPR data permitted to determine the position and get a good identification of the edges of the targets studied. The numeric modeling presented a good accordance with real data reducing the ambiguities in interpretation of results. These results can be used as a reference, and they can be extrapolated for areas where there is no subsurface information.

关键词： Ground Penetrating Radar (GPR) Microwave Tomography Numeric Modeling Concrete Tubes steel Tanks Plastic Tanks IAG/UsP Test site Brazil

Tuning Entanglement Patterns in Qubits Clusters

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Journal of Quantum Information science 2013年第2期3卷 85-92页

作者： F. B. M. dos sant.s A. M. s. Macêdo Departamento de Física Universidade Estadual de Feira de Santana Feira de Santana Brasil Laboratório de Física Teórica e Computacional Departamento de Física Universidade Federal de Pernambuco Recife Brasil

We identify patterns of ground state entanglement, or quantum discord, in qubit clusters with three and four qubits, that are induced by varying the couplings between next-nearest neighbors in the clusters. We show that these entanglement patterns can be associated with continuous multiply connected regions in parameter space, on which entanglement quantifiers, such as the pairwise concurrence, exhibit a particular type of behavior as a function of the couplings between next-nearest neighbors in the cluster. We present the distinct patterns in diagrams in parameter space with continuous boundary lines and we associate each pattern to a specific type of pure quantum correlation. We propose this procedure as a simple method to identify useful classes of pure quantum correlations in qubit networks.

关键词： Entanglement Patterns Qubits

spatial-temporal distribution of fatal yellowing in different oil palm genetic materials in eastern amazon

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Information Processing in Agriculture 2022年第3期9卷 365-377页

作者： Bruno Borella Anhe Artur Vinicius Ferreira dos sant.s Thiago Alan Ferreira da silva Lana Leticia Barbosa de Carvalho Paulo Roberto silva Farias Universidade Federal Rural da Amazonia Geoestatistics Department66.077-830 BelemBrazil Universidade Federal Rural da Amazonia Entomology Department66.077-830 BelemBrazil

Oil palm (Elaeis guineensis Jacq.) is one of the agricultural crops with the greatest potentialfor vegetable oil production in Brazil. However, a disease of unknown etiology popularlyknown as Fatal Yellowin (FY) has caused damage to Brazilian farmers particularly in theeastern region of the Amazon. so, the objective of this study was to evaluate the spatialdependence of FY on three oil palm genotypes, grown for many years in an organic produc-tion system in the Amazon region. The study area had 4104 ha, divided into 139 plots. Ineach plot, the monthly incidence of disease was monitored forming a database. The num-ber of diseased plants per year, number of accumulated diseased plants, number of dis-eased plants per hectare, growth rate of diseased plants and incidence of accumulateddisease were evaluated. The results indicated spatial distribution of the variables adjustedto the gaussian, spherical and exponential models, with predominance of the first *** increases the purpose that FY is caused by biotic factors. The highest range achievedin the study was 2929 m indicating the susceptibility of the tested genotypes. some plotsclose to the river had the highest incidence of the disease on the study, probably associatedwith higher soil moisture.

关键词： Elaeis guineensis Geostatiscal analysis Kriging Palm oil spatial dependence

Yield, Water Use Efficiency and Physiological Characteristic of “Tommy Atkins” Mango under Partial Rootzone Drying Irrigation system

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Journal of Water Resource and Protection 2015年第13期7卷 1029-1037页

作者： Marcelo Rocha dos sant.s Breno Rosa Neves Bismarc Lopes da silva sérgio Luiz Rodrigues Donato Instituto Federal de Educa ç o Ciência e Tecnologia Baiano Campus Guanambi Bahia Brazil

This study was conducted to evaluate the yield, water use efficiency and physiologic characteristics of “Tommy Atkins” mango under partial rootzone drying. The experiment was carried out in an orchard of mango in the irrigated perimeter of Ceraíma, BA. Five treatments and six repetitions were used with one tree per experimental plot: 01—Full Irrigation, 100% of ETc, 02—100% of ETc with frequency of alternance (FA) of 15 days, 03—80% ETc with FA of 15 days, 04—60% of ETc with FA of 15 days, 05—40% ETc with FA of 15 days. The treatments were conductedfrom the beginning of flowering to the harvest of mango in an orchard irrigated by drip. There was no significant reduction in productivity of “Tommy Atkins” mango under PRD up to 40% of ETc and PRD with 40% ETc resulted in greater water use efficiency. There was no significant difference among the averages of photosynthetically active radiation, Qleaf;leaf temperature, Tl;internal CO2 concentration, Ci;transpiration, E;stomatal conductance, gs;photosynthesis, A;carboxylation efficiency, A/Ci;quantum efficiency of photosynthesis, A/Qleaf and instantaneous water use efficiency, A/E between full irrigation and PRD with different water depth. The increase in leaf temperature causes reduction in A/Qleaf and A/E, however, it increases the transpiration. Increased gs results in higher rates of E, A and A/Ci. The use of the PRD with 40% of ETc causes no interference in gas exchange, maintains the yield and increases water use efficiency in “Tommy Atkins” mango tree.

关键词： Irrigation strategy Mangifera Regulated Deficit Irrigation

2D TEM Modeling for a Hydrogeological study in the Paranásedimentary Basin, Brazil

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International Journal of Geosciences 2017年第5期8卷 693-710页

作者： Emerson Rodrigo Almeida Jorge Luís Porsani Fernando Acácio Monteiro dos sant.s Cassiano Antonio Bortolozo Universidade de sã o Paulo Instituto de Astronomia Geofísica e Ciências Atmosféricas Departamento de Geofísica. Rua do Mat&atilde o Butant&atilde S&atilde o Paulo Brazil Universidade de Lisboa-IDL Lisboa Portugal

This work uses 2D TEM (Transient Electromagnetic) modeling for a hydrogeological study in the Paraná sedimentary basin. The study area is located at the northern region of the state of s?o Paulo, Brazil, where groundwater is exploited from two aquifer systems: one sedimentary, shallow, and the other crystalline, deep. The interest in applying the TEM method in this area owes to the high exploitation rates of groundwater from the crystalline aquifer system for irrigation, which is triggering considerable seismic activity locally. This aquifer system is composed of fractured basalt within the serra Geral Formation and is about 120 m deep. Eighty-six TEM soundings were acquired at this location, but in nine cases the data did not fit the modelled curve for 1D geoelectrical models due to the geological complexity of the area. This paper shows 2D geoelectrical modeling results based on the FDTD (Finite Differences in Time Domain) method to explain the lateral resistivity variation within the geological setting. A 2D model was generated for each sounding and compared with 1D inversion models as well as with direct information from wells. The results show some vertical variations of about 10 to 30 meters on the upper interface of the basalt layer from serra Geral Formation. They are located at approximately 60 meters from the center of the soundings. The existence of these 2D structures in the subsurface can be related to the drainage system in the study area. The presence of these structures may indicate a connection between the shallow and deep aquifer systems, acting like a conduit that may contribute to the seismic activity reported.

关键词： Transient Electromagnetic (TEM) 2D Modeling Hydrogeophysics Paraná Basin Brazil