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The assessment of climatic,environmental,and socioeconomic aspects of the Brazilian Cerrado

Ecological Processes 2023年第1期12卷 274-285页

作者： Washington luiz Félix Correia Filho JoséFrancisco de Oliveira-Júnior Dimas de Barros Santiago Hazem Ghassan Abdo Hussein Almohamad Ahmed Abdullah Al Dughairi Carlos Antonio da silva Junior Postgraduate Program in Environmentrics(PPGAmb) Institute of MathematicsStatisticsand Physics(IMEF)Federal University of Rio Grande(FURG)Rio GrandeRio Grande do Sul 96203-900Brazil Institute of Atmospheric Sciences(ICAT) Federal University of Alagoas(UFAL)MaceióAlagoas 57072-260Brazil Postgraduate Program in Biosystems Engineering(PGEB) Federal Fluminense University(UFF)NiteróiRio de Janeiro 24220-900Brazil Postgraduate Program in Meteorology Unidade Acadêmica de Ciências Atmosféricas(UACA)Federal University of Campina Grande(UFCG)Campina GrandeParaíba 58429-140Brazil Geography Department Faculty of Arts and HumanitiesTartous UniversityTartousSyria Geography Department Faculty of Arts and HumanitiesDamascus UniversityDamascusSyria Geography Department Faculty of Arts and HumanitiesTishreen UniversityLat-takiaSyria Department of Geography College of Arabic Language and Social StudiesQassim UniversityBuraydah 51452Saudi Arabia Departamento de Geografia State University of Mato Grosso(UNEMAT)SinopMato Grosso 78555-000Brazil

Background The Cerrado is the most biodiverse savanna and maintains other *** of its significance,this paper evaluated the Brazilian Cerrado’s climatic,environmental,and socioeconomic aspects using remote sensing data and spatial statistics(correlation analysis and principal components analysis—PCA).Following the measures of sample adequacy(MSA)and Kaiser–Meyer–Olkin(KMO)tests,seventeen variables were *** The MSA revealed that the dataset had a good quality(0.76),and nine variables were selected:elevation,evapotranspiration,active fires,Human Development Index(HDI),land use and land cover(LULC;shrubland and cropland/rainfed),rainfall(spring and autumn),and *** correlation matrix indicated a positive(negative)association between HDI and autumn rainfall(HDI and active fires)with a value of 0.77(-0.55).The PCA results determined which three principal components(PC)were adequate for extracting spatial patterns,accounting for 68.02%of the total variance with respective values of 38.59%,16.89%,and 12.5%.Due to economic development and agribusiness,Cerrado’s northern(central,western,and southern)areas had negative(positive)score HDI values,as shown in ***(rainfall—spring and fall)and environmental(cropland/rainfed and shrubland)aspects dominated the PC2,with negative scores in northern and western portions due to the transition zone between Amazon and Cerrado biomes caused by rainfall *** the other hand,environmental aspects(LULC-shrubland and elevation)influenced the PC3;areas with high altitudes(>500 m)received a higher *** Agricultural expansion substantially affected LULC,leading to deforestation-caused suppression of native vegetation.

关键词： Environment Agribusiness Active fire Human Development Index Land use and land cover

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Structural phase relations in perovskite-structured BiFeO_(3)-based multiferroic compounds

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Journal of Advanced Ceramics 2013年第2期2卷 103-111页

作者： Valdirlei Fernandes FREITAS Gustavo Sanguino DIAS Otávio Algusto PROTZEK Diogo Zampieri MONTANHER Igor Barbosa CATELLANI Daniel Matos silva luiz Fernando CÓTICA Ivair Aparecido dos SANTOS UEM-Universidade Estadual de Maringá GDDM-Grupo de Desenvolvimento de Dispositivos MultifuncionaisDepartamento de FísicaMaringáBrazil

In this review,the state of the art in understanding the structural phase relations in perovskite-structured BiFeO_(3)-based polycrystalline solid solutions is presented and *** about the close relation between the structural phase and overall physical properties of the reviewed systems are pointed out and *** is shown that,by adjusting the structural symmetric arrangement,the ferroelectric and magnetic properties of BiFeO_(3)-based polycrystalline solid solutions can be tuned to find specific multifunctional ***,an intrinsic mechanism linking structural arrangement and physical properties cannot be identified,revealing that this subject still deserves further discussion and investigation.

关键词： bismuth ferrite ferroelectrics multiferroics

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Cyclone as a Sugar Cane Bagasse Dryer

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Chinese Journal of Chemical Engineering 2004年第6期12卷 826-830页

作者： Jefferson luiz Gomes Correa Daniel Rezende Graminho Maria Aparecida silva Silvia Azucena Nebra Faculty of Mechanical Engineering State University of Campinas P.O. Box 6122 Campinas/SP 13083-970 BrazilFaculty of Mechanical Engineering State University of Campinas P.O. Box 6122 Campinas/SP 13083-970 BrazilFaculty of Chemical Engineering State University of Campinas P.O. Box 6066 Campinas/SP 13083-970 BrazilFaculty of Mechanical Engineering State University of Campinas P.O. Box 6122 Campinas/SP 13083-970 Brazil

Drying of sugar cane bagasse was theoretically and experimentally studied ina cyclone. The experiments were carried out using hot air as drying agent. The influence of thecyclone conical part was studied. It was shown that the conical part has a great influence on theparticle residence time and, consequently, on moisture reduction. Experimental results were alikeindustrial ones. CFX 4.4 from AEA Technology was used to simulate some experiments. Simulated andexperimental results were close and showed that the presented model leads to a good prediction.

关键词： cyclone cyclonic dryer sugar cane bagasse particle residence time dryer energy

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Advances in Tropical Soil Characterization via Portable X-Ray Fluorescence Spectrometry

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Pedosphere 2019年第4期29卷 468-482页

作者： Elen A. silva David C. WEINDORF Sergio H. G. silva Bruno T. RIBEIRO Giovana C. POGGERE Teotonio S. CARVALHO Mariana G. M. GONQALVES luiz R. G. GUILHERME Nilton CURI Department of Soil Science Federal University of Lavras Lavras 37200-000 (Brazil) Department of Plant and Soil Science Texas Tech University Texas 79409-2122 (USA)

Portable X-ray fluorescence(pXRF) spectrometers can be used to determine the elemental composition easily, rapidly, and without using chemical reagents, which is very important for tropical regions due to the lack of detailed soil characterization data. Moreover,pXRF data can be used to predict the results of more expensive, time-consuming, and conventional laboratory analyses. This study sought to determine the elemental composition of various soil profiles using pXRF. Two operational modes(Trace Mode and General Mode) and two scanning time(30 and 60 s) were assessed to determine their effects on the correlation of pXRF dataset with respect to conventional inductively coupled plasma(ICP)-optical emission spectrometry analysis. This relationship has been reported in previous studies, however, few studies were performed on tropical soils, which are unique. Furthermore, such relationships establish the viability of developing prediction models directly from pXRF data. Linear regression was applied to develop calibration models for the prediction of ICP analysis results and exchangeable and available elemental contents based on pXRF data. High coefficients of determination(R^2) were obtained for Ca(0.87), Cu(0.90), Fe(0.95), Mn(0.85), Cr(0.95), V(0.72), and Ni(0.90), with adequate validation. Statistically significant results were not found for Al, K, Zn, Ti, and Zr. The models predicting the exchangeable Ca based on the total Ca from p XRF reached an R^2 of up to 0.85. Operational modes influenced the pXRF results. Our results illustrate that pXRF holds great promise for tropical soil characterization and the development of prediction models, justifying the need for larger-scale studies in tropical countries worldwide.

关键词： elemental composition exchangeable Ca inductively coupled plasma operational mode prediction models scanning time soil analysis total elemental content

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Proximal sensor-enhanced soil mapping in complex soil-landscape areas of Brazil

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Pedosphere 2021年第4期31卷 615-626页

作者： Sérgio H.G.silva David C.WEINDORF Wilson M.FARIA Leandro C.PINTO Michele D.MENEZES luiz R.G.GUILHERME Nilton CURI Department of Soil Science Federal University of LavrasLavras 37200-000(Brazil) Department of Earth and Atmospheric Sciences Central Michigan UniversityMount Pleasant 48858(USA)

Portable X-ray fluorescence(pXRF) spectrometry and magnetic susceptibility(MS) via magnetometer have been increasingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many countries with tropical soils. The objective of this study was to use proximal soil sensor data associated with terrain variables at varying spatial resolutions to predict soil classes using the Random Forest(RF) algorithm. The study was conducted on a 316-ha area featuring highly variable soil classes and complex soil-landscape relationships in Minas Gerais State, Brazil. The overall accuracy and Kappa index were evaluated using soils that were classified at 118 sites, with 90 being used for modeling and 28 for validation. Digital elevation models(DEMs) were created at 5-, 10-, 20-, and 30-m resolutions using contour lines from two sources. The resulting DEMs were processed to generate 12 terrain variables. Total Fe, Ti, and SiO_(2) contents were obtained using pXRF, with MS determined via a magnetometer. Soil class prediction was performed using the RF algorithm. The quality of the soil maps improved when using only the five most important covariates and combining proximal sensor data with terrain variables at different spatial resolutions. The finest spatial resolution did not always provide the most accurate maps. The high soil complexity in the area prevented highly accurate predictions. The most important variables influencing the soil mapping were MS, Fe, and Ti. Proximal sensor data associated with terrain information were successfully used to map Brazilian soils at variable spatial resolutions.

关键词： magnetic susceptibility magnetometer portable X-ray fluorescence spectrometer soil class soil spatial analysis spatial resolution terrain variables

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Litterfall dynamics and soil carbon and nitrogen stocks in the Brazilian palm swamp ecosystems

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Forest Ecosystems 2020年第3期7卷 499-510页

作者： Gracielle de Brito Sales Taynan Aquilles Marinho Lessa Daniela Aparecida Freitas Maria das Dores Magalhães Veloso Maria Ligia de Souza silva luiz Arnaldo Fernandes Leidivan Almeida Frazão Instituto de Ciências Agrárias Universidade Federal de Minas GeraisAvenida Universitária1000Montes ClarosMG39404-547Brazil Universidade Estadual de Montes Claros Avenida Professor Rui Braga S/NMontes ClarosMG39401-089Brazil Universidade Federal de Lavras Campus UniversitárioCP 3037LavrasMG37299-000Brazil

Background: This study aimed to determine the litterfall production, accumulation, decomposition rate and nutrient stocks, and to estimate the soil carbon(C) and nitrogen(N) stocks in three palm swamp ecosystems with different land use intensities in the Southeast of ***: Three palm swamp ecosystems with different land use intensities were evaluated: Agua Doce(AD),conserved area;Capivara(CV), area with small agricultural practices;and Buriti Grosso(BG), area with an intensive land use. Produced and accumulated litterfall from the Cerrado areas surrounding the palm swamps were collected from October 2014 to September 2015, and the Ca, Mg, K, and P concentrations were determined in the dry and rainy seasons. Soil samples were collected in the surrounding Cerrado and within the palm swamps until 100 cm soil depth to determine bulk density and soil C and N contents and ***: Annual litterfall production in the Cerrado surrounding palm swamps was similar in AD(3.58 Mg·ha^-1·year^-1) and CV(3.79 Mg·ha^-1·year^-1), and was lower in BG(2.84 Mg·ha^-1·year^-1), and was more intense during the dry season. Furthermore, litterfall accumulation was higher in CV(7.12 Mg·ha^-1·year^-1) and BG(6.75 Mg·ha^-1·year^-1), culminating in lower decomposition rates. AD showed the highest decomposition rate(0.60) due to its vegetation structure and conservation. The macronutrient contents from the production and accumulated litterfall had a low influence of the land use, decreasing in the following order: Ca > K > Mg > P. Soils in CV and BG palm swamp areas showed higher values of C and N contents, due to the use of land for agricultural crops and cattle raising in an extensive(rangeland) system. The BG palm swamp, showed the highest C(124.03 Mg·ha^-1) and N(10.54 Mg·ha^-1) stocks due to the land use history with different agricultural practices over ***: The litterfall dynamics in the Cerrado surrounding palm swamps was more affected by climatic variables t

关键词： Nutrient cycling Soil fertility Soil organic matter Decomposition rate

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Heterogeneity in the Second Internal Transcribed Spacer (ITS2) of rDNA in the Genetically Distinct Metopolophium dirhodum Isofemale Lineages (Hemiptera: Aphididae)

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Advances in Entomology 2014年第4期2卷 194-201页

作者： Marcelo Lopes-da-silva luiz Gonzaga Esteves Vieira Plant Quarantine Laboratory Embrapa Genetic Resources and Biotechnology Brazilian Agriculture Research Corporation (Embrapa) Brasília DF Brazil University of Western São Paulo (Unoeste) Presidente Prudente Brazil

The aim of this study was to investigate the level of evolutionary divergence among five isofemale lineages of Metopolophium dirhodum Walker (Hemiptera: Aphididae) using sequences of the Internal Transcribed Spacer (ITS) of ribosomal DNA (rDNA). These isofemalelineages were derived from parthenogenetic females, previously genetically characterized by having strong association of RAPD (Random Amplified Polymorphic DNA) molecular markers and host plant preference. Out of 25 sequences, only 17 containing ITS2 (the second spacer) were used for analysis due to their quality. Within 250 nucleotide sites originated by multiple alignments, 10.4% were variable, with the predominance of indels over substitutions. The average of nucleotide diversity (π) within isofemale lineages was similar to the diversity found among all isofemale lineages. The topology inferred by the Neighbor-Joining method showed that no evolutionary divergence inferred by ITS2 sequences among isofemale lineages typified by RAPD could be associated with host preference. The ITS2 sequence differences found within lineages and their causes are discussed.

关键词： Aphid Clones Molecular Evolution DNA

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Using Luhn’s Automatic Abstract Method to Create Graphs of Words for Document Visualization

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Social Networking 2014年第2期3卷 65-70页

作者： luiz Cláudio Santos silva Renelson Ribeiro Sampaio Faculdade de Tecnologia SENAI Cimatec Salvador Brazil

Visualization methods for single documents are either too simple, considering word frequency only, or depend on syntactic and semantic information bases to be more useful. This paper presents an intermediary approach, based on H. P. Luhn’s automatic abstract creation algorithm, and intends to aggregate more information to document visualization than word counting methods do without the need of external sources. The method takes pairs of relevant words and computes the linkage force between them. Relevant words become vertices and links become edges in the resulting graph.

关键词： Text Visualization Graph of Words

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The Emerging Issue of Solid Waste Disposal Sites Emissions in Developing Countries: The Case of Brazil

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Journal of Environmental Protection 2014年第10期5卷 886-894页

作者： André luiz Bufoni Marcia da silva Carvalho Luciano Basto Oliveira luiz Pinguelli Rosa Accounting Department Federal University of Rio de Janeiro Rio de Janeiro Brazil Energy Planning Program Federal University of Rio de Janeiro Rio de Janeiro Brazil IVIG—International Virtual Institute of Global Changes Federal University of Rio de Janeiro Rio de Janeiro Brazil

While the main concerns with municipal solid waste in developed countries like the European Union and the United States are to reduce and recycle the energy recover in order to drastically reduce the residues disposal to landfill, for developing countries the targets on waste management are much more basic. This seems to be the case in Brazil that with a new regulation, it still attempts to eradicate the inadequate waste disposal for open dumps. Thus, the aim of this paper is to depict the context, the criteria and discuss the strategies used for: the municipalities achieve the goals and adhere the plan;choice and configuration of disposal sites;and economic instruments adopted and bringing the whole scenario to discussion, including methane emissions inventory thru the case study of the Rio de Janeiro State. The Rio de Janeiro State municipal solid waste management scenario has drastically changed in last five years from 9% of residues sent to adequate destinations, to the perspective of eradication of open dumps before the end of 2014. The results indicate that only adequate disposal of waste is mandatory with the prevalence of the sanitation approach. The evidences also indicate that planning goals to reduce waste are modest and the landfill gas recover is generally accepted as the optimal solution. This paper concludes that, unless the stakeholders add to the plan a more aggressive policy to increment, the competitiveness of other waste technologies that favor the landfilling reduction and energy recover, Rio de Janeiro State will face the increase of landfill numbers and sizes, management cost, environmental and leachate impact, post-closure care expenses, contaminating life-span, and methane emissions.

关键词： Landfill Gas Strategy Greenhouse Gas Waste Management

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Different risk factors influence peptic ulcer disease development in a Brazilian population

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World Journal of Gastroenterology 2012年第38期18卷 5404-5411页

作者： Rodrigo Buzinaro Suzuki Rodrigo Faria Cola Larissa Tranquilino Bardela Cola Camila Garcia Ferrari Fred Ellinger Altino luiz Therezo Luis Carlos da silva André Eterovic Márcia Aparecida Sperana Department of Genotyping Hemocenter Marilia Medical School Marilia 17519-030 So Paulo Brazil Center for Natural and Human Sciences Universidade Federal do ABC Santo André 09210-170 So Paulo Brazil Department of Molecular Biology Marilia Medical School Marilia 17519-030 So Paulo Brazil Department of Pathology Marilia Medical School Marilia 17519-030 So Paulo Brazil

AIM: To investigate age, sex, histopathology and Helicobacter pylori (H. pylori) status, as risk factors for gastroduodenal disease outcome in Brazilian dyspeptic *** submitted to upper gastroscopy at Hospital das Clinicas of Marilia, antral biopsy specimens were obtained and subjected to histopathology and H. pylori diagnosis. All patients presenting chronic gastritis (CG) and peptic ulcer (PU) disease localized in the stomach, gastric ulcer (GU) and/or duodenal ulcer (DU) were included in the study. Gastric biopsies (n = 668) positive for H. pylori by rapid urease test were investigated for vacuolating cytotoxin A (vacA ) medium (m) region mosaicism by polymerase chain reaction. Logistic regression analysis was performed to verify the association of age, sex, histopathologic alterations, H. pylori diagnosis and vacA m region mosaicism with the incidence of DU, GU and CG in patients. RESULTS: Of 1466 patients submitted to endoscopy, 1060 (72.3%) presented CG [male/female = 506/554; mean age (year) ± SD = 51.2 ± 17.81], 88 (6.0%) presented DU [male/female = 54/34; mean age (year) ± SD = 51.4 ± 17.14], and 75 (5.1%) presented GU [male/female = 54/21; mean age (year) ± SD = 51.3 ± 17.12] and were included in the comparative analysis. Sex and age showed no detectable effect on CG incidence (overall c 2 = 2.1, P = 0.3423). Sex [Odds ratios (OR) = 1.8631, P = 0.0058] but not age (OR = 0.9929, P = 0.2699) was associated with DU and both parameters had a highly significant effect on GU (overall c 2 = 30.5, P < 0.0001). The histopathological results showed a significant contribution of ageing for both atrophy (OR = 1.0297, P < 0.0001) and intestinal metaplasia (OR = 1.0520, P < 0.0001). Presence of H. pylori was significantly associated with decreasing age (OR = 0.9827, P < 0.0001) and with the incidence of DU (OR = 3.6077, P < 0.0001). The prevalence of m1 in DU was statistically significant (OR = 2.3563, P = 0.0018) but not in CG (OR = 2.678, P = 0.0863) and G

关键词： Helicobacter pylori Gastric ulcer disease Duodenal ulcer disease Gastric atrophy Helicobacter pylori vacuolating cytotoxin A medium region mosaicism

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