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au:QUEIROZ, DANIEL M. DE

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VIBRATION TRANSMISSIBILITY OF THE COFFEE FRUIT-PEDUNCLE SYSTEM: A FORCED VIBRATION STUDY OF HIGH FREQUENCY AIMING MECHANICAL HARVESTING
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Villibor, Geice P.

; Santos, Fábio L.

; Queiroz, Daniel M.

; Khoury Junior, Joseph K

; Pinto, Francisco A. C.

Engenharia Agrícola

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2023, Volume 43 Nº 1 elocation e20220201

Resumo: En | Texto: En | PDF: En

ABSTRACT Semi-mechanized and mechanized harvesting use machines that promote the transference of vibrational energy and impact to achieve the detachment of coffee fruits. The aim of this study was to evaluate the vibration transmissibility in coffee fruit-peduncle systems, using high-speed cameras, submitted to high frequency harmonic excitation in different combinations between frequency and amplitude of vibration, identifying working ranges suitable to perform selective harvesting. Vibration transmissibility was determined for the coffee fruit-peduncle systems, for the maturation stages unripe and ripe that were subjected to a sinusoidal harmonic displacement, in which the input parameters were frequency (35, 45 and 55 Hz) and peak-to-peak amplitude (3.5, 5.0 and 6.5 mm). An experiment was used to study the effect of frequency and amplitude on vibration transmissibility in a completely randomized design in a factorial scheme 3 x 3 x 2, with three replications. The frequency of 35 Hz, associated with the amplitudes 3.5-6.5 mm, was the one that most influenced the results of vibration transmissibility. For the frequency of 55 Hz and amplitude of 6.5 mm, in the ripe maturation stage, the vibration transmissibility was higher than 1.0, which could be a suitable combination for selective coffee harvesting.

https://doi.org/10.1590/1809-4430-eng.agric.v43n1e20210201/2023

The psyllid fauna (Hemiptera: Psylloidea) of vegetable fields in Brazil
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Kuhn, Taciana M. de A.

; Burckhardt, Daniel

; Queiroz, Dalva L.

; Antolínez, Carlos A.

; Teresani, Gabriela R.

; Lopes, João R. S.

Revista Brasileira de Entomologia

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2023, Volume 67 Nº 1 elocation e20220036

Resumo: En | Texto: En | PDF: En

ABSTRACT Some psyllids transmit 'Candidatus Liberibacter solanacearum' (Lso), the causal agent of devastating plant diseases of cultivated Solanaceae and Apiaceae. The recent detection of Bactericera cockerelli and Lso in Ecuador seriously threatens these crops in South America. There, neither the role of native psyllids in the Lso epidemiology nor the psyllid fauna of vegetables are known. With the aim to identify potential vectors and risk scenarios for the spread of Lso in South America, a survey of the psyllid fauna of Solanaceae and Apiaceae crops and associated weeds was conducted in Brazil. Samples were taken at 29 localities in four states. A total of 2857 specimens were sampled, representing at least 37 species of 23 genera and seven families. The most frequent species on carrot, chilli pepper and potato were Russelliana solanicola, R. capsici and Isogonoceraia divergipennis, respectively. Immatures of R. capsici were found on chilli pepper and of R. solanicola on carrot and potato, confirming these plants as hosts. The two psyllid species have been suspected previously to transmit plant pathogens of unknown identity. Russelliana solanicola is one of the few polyphagous species. Here the species is reported for the first time from carrot. Recent collections in Rio Grande do Sul suggest that Solanum laxum represents the original host of R. capsici, which subsequently shifted to chilli pepper. Both, adaptation to agricultural crops and the possibility of ability to transmit pathogens, make the two Russelliana species dangerous potential vectors of Lso and other plant pathogens in South America.

https://doi.org/10.1590/1806-9665-rbent-2022-0036

SOIL PHOSPHORUS TEST USING A LOW-COST SPECTROPHOTOMETER AND MACHINE LEARNING
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Mayrink, Grégory O.

; Queiroz, Daniel M. de

; Coelho, Andre L. de F.

; Valente, Domingos S. M.

Engenharia Agrícola

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2022, Volume 42 Nº 6 elocation e20210228

Resumo: En | Texto: En | PDF: En

ABSTRACT Phosphorus concentration is one of the main attributes determined in laboratory analyses of soil samples collected in the field. The objective is to develop a soil phosphorus test using a low-cost spectrophotometer and a machine learning technique. For reflectance measurements, a low-cost system consisting of a Sparkfun AS7625x spectrophotometer and an Arduino Uno is used. Ion exchange resins under standard saturated solutions and modified conditions are used to extract phosphorus ions from the soil samples. Reflectance and phosphorus concentrations determined by the reference method are used in the training and testing of a machine learning. A modification procedure of the ion-exchange resin saturation solution allows the establishment of a strong correlation between the reflectance in 18 spectral bands and P concentration of the soil samples. The obtained model uses five reflectance of the modified resins at wavelengths of 410, 460, 560, 705, and 645 nm to predict the phosphorus concentration. This model presents an R2t accuracy of 0.97 in the training stage with an R2v of 0.96, RMSEv of 9.05, and ratio of prediction to deviation) of 3.81 in the test step.

https://doi.org/10.1590/1809-4430-eng.agric.v42n6e20210228/2022

Development of a TD-NMR Method to Monitor Brazil Nuts Oil Content: A Green and Low-Cost Based Approach
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Ribeiro, Úrsula A.

; Queiroz, Leonardo C.

; Marassi, Agide G.

; Carvalho, André S.

; Barros, Gabriel A.

; Consalter, Daniel M.

; Bezerra, Jaqueline A.

; Santos, Alan D. C.

; Colnago, Luiz Alberto

; Machado, Marcos B.

Journal of the Brazilian Chemical Society

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Jul 2021, Volume 32 Nº 7 Páginas 1405 - 1412

Resumo: En | Texto: En | PDF: En

Growth in the international popularity of Brazil nuts oil (Bertholletia excelsa, Bonpl.) has demanded a closer look at quality aspects of the nuts. In this context, time-domain 1H nuclear magnetic resonance spectroscopy (TD-NMR) can be a useful tool for assessing the lipid portion of such matrices. In this work, a TD-NMR method was developed and validated to assess the oil content directly from Brazil nuts following the ISO 10565:1998 and DOQ-CGCRE-008. Full validation was addressed covering the working range from 0.67 to 25.00 g (coefficient of determination, R2= 0.9993). Limits of detection (LOD) and quantification (LOQ) were 0.20 and 0.67 g, respectively. The repeatability and intermediate precision assays met the guide requirements. Oil contents obtained in two laboratories (different equipment) were statistically similar (66.93 ± 4.69 and 70.13 ± 4.15%), highlighting the method’s robustness. The developed approach has the potential to be adopted as an industrial reference method for in situ monitoring of Brazil nuts oil contents.

https://doi.org/10.21577/0103-5053.20210039 105 downloads

SPATIAL VARIABILITY OF SOIL APPARENT ELECTRICAL CONDUCTIVITY - EFFECT OF THE NUMBER OF SUBSAMPLES
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Sousa, Emanoel Di Tarso dos S.

; Queiroz, Daniel M. de

; Rosas, Jorge T. F.

; Nascimento, Amélia L. do

Engenharia Agrícola

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Mai 2021, Volume 41 Nº 3 Páginas 396 - 401

Resumo: En | Texto: En | PDF: En

ABSTRACT Soil apparent electrical conductivity (ECa) sensors have been used to detect spatial variability because they correlate with soil attributes. Studies with soil attributes have shown that the number of subsamples and sampling points influences mapping. However, there are no studies that investigated the influence of sampling or subsampling density on ECa maps. Therefore, this study verified the influence of ECa readings per sample point on the semivariance and kriging analysis. The data were collected from an area (2.5 ha) of coffee plants. One hundred sampling points were measured considering 20 readings each. 1, 5, 10, 15, and 20 sample point readings were tested. The influence of the number of readings per sampling point on the ECa mapping was determined using linear regression analysis at a significance level of 5%. The results obtained showed that ECa readings per sampling point significantly influence ECa maps. In addition, they demonstrated that reducing the number of readings per sampling point increases prediction errors by kriging. Thus, ECa maps determined with the highest readings per sampling point were mostly accurate.

https://doi.org/10.1590/1809-4430-eng.agric.v41n3p396-401/2021 132 downloads

Sensor system for acquisition of vegetation indexes
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Silva, Thales M. de A.

; Valente, Domingos S. M.

; Pinto, Francisco de A. de C.

; Queiroz, Daniel M. de

; Santos, Nerilson T.

Revista Brasileira de Engenharia Agrícola e Ambiental

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Abr 2021, Volume 25 Nº 4 Páginas 264 - 269

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

RESUMO Os índices de vegetação são importantes indicadores da saúde e produtividade das culturas agrícolas. Dentre os tipos de sensores, os sensores proximais podem ser utilizados para tomada de decisão em tempo real. Dessa forma, o objetivo deste estudo foi desenvolver um sistema sensor proximal, com base em fototransistor, para obtenção e armazenamento dos índices de vegetação: NDVI (Índice de Vegetação da Diferença Normalizada), SR (Razão Simples), WDRVI (Índice de Vegetação de Larga Escala Dinâmica), SAVI (Índice de Vegetação Ajustado ao Solo) e OSAVI (Índice de Vegetação Ajustado ao Solo Otimizado). O sistema sensor foi desenvolvido utilizando um circuito analógico para realizar a aquisição de dados de reflectância das bandas do vermelho e infravermelho próximo. O sistema sensor foi calibrado, utilizando grama Zoysia japonica, para ajustar seus valores aos de um espectroradiômetro. Desenvolveu-se um algoritmo que calcula os índices de vegetação e armazena os resultados em um arquivo. Avaliou-se a correlação de Pearson entre os índices de vegetação obtidos com o sistema sensor e o espectroradiômetro. Os índices de vegetação apresentaram correlação de Pearson superiores a 0,92 com os valores estimados pelo espectroradiômetro. Nas condições analisadas, o sistema sensor proposto pode ser utilizado na determinação de todos os índices de vegetação abordados.

ABSTRACT Vegetation indexes are important indicators of the health and yield of agricultural crops. Among the sensors used to evaluate vegetation indexes, proximal sensors can be used for real-time decision-making. Thus, the objective of this study was to develop a proximal sensor system based on phototransistors to acquire and store the following vegetation indexes: normalized difference vegetation index, simple ratio, wide dynamic range vegetation index, soil-adjusted vegetation index, and optimized soil-adjusted vegetation index. The sensor system was developed using an analog circuit to acquire reflectance data from red and near-infrared bands. The sensor system was calibrated according to the results of a spectroradiometer, using Zoysia japonica grass as the target. An algorithm that calculates and stores vegetation indexes in a file was developed. The Pearson correlation between the vegetation indexes obtained with the sensor system and the spectroradiometer was evaluated. The vegetation indexes presented a Pearson correlation higher than 0.92 to the estimated values by the spectroradiometer. Under the evaluation conditions, the proposed sensor system could be used to determine all vegetation indexes evaluated.

https://doi.org/10.1590/1807-1929/agriambi.v25n4p264-269 352 downloads

Mesquite (Prosopis juliflora) extract as a phytogenic additive for sheep finished on pasture in the semiarid region
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Férrer, Juliana P.

; da Cunha, Márcio V.

; dos Santos, Mércia V.F.

; Torres, Thaysa R.

; da Silva, José R.C.

; Véras, Robson M.L.

; da Silva, Daniel C.

; da Silva, Alisson H.

; Queiroz, Luana M.D.

; Férrer, Moisés T.

; Neto, Elias L.S.

; Jaramillo, David M.

; de Souza, Evaristo J.O.

Chilean journal of agricultural research

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Mar 2021, Volume 81 Nº 1 Páginas 14 - 26

Resumo: En | Texto: En | PDF: En

ABSTRACT Phytogenic additives are organic molecules that also improve ruminal fermentation, turning the supplemented individuals into more productive animals, without damage the population welfare. The objective of this study was to evaluate the effects of mesquite (Prosopis juliflora [Sw.] DC.) extract as phytogenic additive for sheep finished on pasture in the Brazilian Northeast semiarid region. Twenty-four intact lambs (Santa Ines × Dorper F1 crossbred) were used, with an initial body weight of 23.00 ± 1.83 kg. The experiment was carried out in a complete randomized design with four treatments and six replicates. Treatments consisted of four diets: Pasture and no supplementation; grazing pasture and phytogenic additive; pasture, supplementation with Tifton 85 hay, and concentrate; and pasture, phytogenic additive, and supplementation with Tifton 85 hay and concentrate. Prior to supplementation, animals received the phytogenic additive according to treatment. There were nonsignificant differences for nutrient intake and behavior patterns (P > 0.05). However, additive intake derived from mesquite provided an increase (P < 0.05) in digestibility (14.40% total digestible nutrients), N balance (27.12% retained N:ingested N) and performance (8.82% final body weight, 21.81% total weight gain, and 30.81% average daily gain) compared to animals consuming only pasture in rainy period. Thus, the use of mesquite extract as phytogenic additive is recommended for sheep finished on pasture in the Brazilian semiarid region.

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COMPARING A SINGLE-SENSOR CAMERA WITH A MULTISENSOR CAMERA FOR MONITORING COFFEE CROP USING UNMANNED AERIAL VEHICLES
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Gomes, Amanda P. A.

; Queiroz, Daniel M. de

; Valente, Domingos S. M.

; Pinto, Francisco de A. de C.

; Rosas, Jorge T. F.

Engenharia Agrícola

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Fev 2021, Volume 41 Nº 1 Páginas 87 - 97

Resumo: En | Texto: En | PDF: En

ABSTRACT There exist two options for digital cameras that can capture the near-infrared (NIR) band. Conventional red–green–blue (RGB, visible bands) cameras with a single sensor provide NIR band visibility based on the removal of the internal NIR-blocking filter. Alternatively, multisensor cameras exist that have a specific sensor for each band. The modified RGB cameras are of a lower price. In this context, the objective of this study was to compare the performance of a modified RGB camera with that of a multisensor camera for obtaining the normalized difference vegetation index (NDVI) in an area with coffee cultivations. A multispectral camera with five sensors and another camera with only one sensor were used. The NDVI of the coffee field was also measured using the GreenSeeker handheld NDVI sensor manufactured by Trimble. The images were calibrated radiometrically based on the targets in shades of gray made of napa, and the NDVI was calculated after image calibration. The calibration curves showed a high coefficient of determination. The NDVI value obtained with the calibrated images from the cameras showed a significant correlation with the values obtained by the GreenSeeker NDVI sensor, making it possible to obtain the variability pattern of the vegetation index. However, the NDVI obtained using the multisensor camera was closer to the NDVI obtained by the GreenSeeker NDVI sensor.

https://doi.org/10.1590/1809-4430-eng.agric.v41n1p87-97/2021 634 downloads

O “Princípio de Pascal” nos livros do PNLD 2018: uma análise crítica multicontextual (histórica e conceitual)
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Hidalgo, Juliana M.

; Queiroz, Daniel de Medeiros

; Anselmo, Dory H.A.L.

Revista Brasileira de Ensino de Física

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2021, Volume 43 elocation e20210064

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Esse trabalho apresenta uma avaliação crítica multicontextual, histórica e conceitual, do Princípio de Pascal nos livros didáticos de Física aprovados no Programa Nacional do Livro Didático (PNLD) 2018. A análise realizada levou em consideração os seguintes aspectos: o enunciado do Princípio de Pascal sob o ponto de vista conceitual; relações entre ciência e tecnologia, tendo em vista dispositivos relacionados ao Princípio; fontes históricas primárias e secundárias relacionadas ao desenvolvimento do Princípio de Pascal; fundamentação historiográfica e apontamentos da legislação educacional para a inserção didática da História e da Filosofia da Ciência. Foram notadas inconsistências no que diz respeito à aplicabilidade do Princípio de Pascal, visões simplistas sobre a ciência e sobre as relações entre ciência e tecnologia, distorções históricas, anacronismos e abordagens historicamente descontextualizadas. Em face do referido cenário, são apontadas sugestões para uma inserção didática mais adequada.

This paper presents a multicontextual, historical and conceptual, critical analysis of Pascal’s Principle in Brazilian Physics textbooks from Programa Nacional do Livro Didático (PNLD) 2018. The analysis considered the following aspects: the statement of Pascal’s Principle from a conceptual perspective; relations between science and technology, in view of devices associated to the Principle; primary and secondary historical sources related to the development of Pascal’s Principle; historiographical foundation; and notes from Brazilian educational legislation concerned to didactic insertion of History and Philosophy of Science. We noticed inconsistencies regarding the applicability of Pascal’s Principle, simplistic views on science and on the relationship between science and technology, historical distortions, anachronisms, and historically decontextualized approaches. Suggestions are made considering this scenario, aiming at a more adequate didactic insertion.

https://doi.org/10.1590/1806-9126-rbef-2021-0064

10.

Baryon Acoustic Oscillations from Integrated Neutral Gas Observations: an instrument to observe the 21cm hydrogen line in the redshift range 0.13 < z < 0.45 – status update
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WUENSCHE, CARLOS A.

; ABDALLA, ELCIO

; ABDALLA, FILIPE

; BAROSI, LUCIANO

; WANG, BIN

; AN, RUI

; BARRETOS, JOÃO A. M.

; BATTYE, RICHARD

; BRITO, FRANCISCO A.

; BROWNE, IAN

; CORREIA, DANIEL

; COSTA, ANDRÉ A.

; DELABROUILLE, JACQUES

; DICKINSON, CLIVE

; FENG, CHANG

; FERREIRA, ELISA G. M.

; FORNAZIER, KARIN

; DE GASPERIS, GIANCARLO

; GUTIERREZ, PRISCILA

; HARPER, STUART

; LANDIM, RICARDO G.

; LICCARDO, VINCENZO

; MA, YIN-ZHE

; MACHADO, TELMO

; MAFFEI, BRUNO

; MARINS, ALESSANDRO

; MENDES, MILENA M. M.

; MERICIA, EDUARDO

; MONSTEIN, CHRISTIAN

; MOTTA, PABLO

; NOVAES, CAMILA

; OTOBONE, CARLOS H.

; PEEL, MICHAEL

; QUEIROZ, AMILCAR R.

; RADCLIFFE, CHRISTOPHER

; REMAZEILLES, MATHIEU

; RIBEIRO, RAFAEL M. G.

; SANG, YU

; SANTOS, JULIANA F. R.

; SANTOS, LARISSA

; SANTOS, MARCELO. V.

; SHAN, CHENXI

; SILVA, GUSTAVO B.

; VIEIRA, FREDERICO

; VIEIRA, JORDANY

; VILLELA, THYRSO

; XIAO, LINFENG

; YANG, WEIQIANG

; ZHANG, JIAJUN

; ZHANG, XUE

; ZHU, ZENGHAO

Anais da Academia Brasileira de Ciências

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2021, Volume 93 elocation e20201096

Resumo: En | Texto: En | PDF: En

Abstract BINGO (BAO from Integrated Neutral Gas Observations) is a unique radio telescope designed to map the intensity of neutral hydrogen distribution at cosmological distances, making the first detection of Baryon Acoustic Oscillations (BAO) in the frequency band 980 MHz - 1260 MHz, corresponding to a redshift range 0.127 < z < 0.449. BAO is one of the most powerful probes of cosmological parameters and BINGO was designed to detect the BAO signal to a level that makes it possible to put new constraints on the equation of state of dark energy. The telescope will be built in Paraíba, Brazil and consists of two \thicksim 40m mirrors, a feedhorn array of 50 horns, and no moving parts, working as a drift-scan instrument. It will cover a 15 ^{\circ} ∘ declination strip centered at \sim \delta ∼ δ =-15 ^{\circ} ∘, mapping \sim ∼ 5400 square degrees in the sky. The BINGO consortium is led by University of São Paulo with co-leadership at National Institute for Space Research and Campina Grande Federal University (Brazil). Telescope subsystems have already been fabricated and tested, and the dish and structure fabrication are expected to start in late 2020, as well as the road and terrain preparation.

https://doi.org/10.1590/0001-3765202120201096 413 downloads

11.

Relationship between the hsa miR 150-5p and FTO gene expression in white subcutaneous adipose tissue with overweight/obesity, lipid profile and glycemia
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MORAES, VITOR N.

; QUEIROZ, ANDRÉ L.

; MARTONE, DANIEL

; RODRIGUES, JHENNYFER A.L.

; GOMES, MATHEUS M.

; SALGADO JÚNIOR, WILSON

; BUENO JR, CARLOS ROBERTO

Anais da Academia Brasileira de Ciências

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2020, Volume 92 Nº 4 elocation e20200249

Resumo: En | Texto: En | PDF: En

Abstract The overweight population is growing in the world, and the search for obesity-associated mechanisms is important for a better understanding of this disease. Few studies with the FTO gene and miRs show how they associate to obesity and how they can impact this disease. The aim of this study was to verify the relationship between the FTO gene and the hsa-miR-150-5p expression with overweight/obesity, lipid profile, and fast blood glucose. Men and women (18 years older or above), with body mass index ≥ 18.5 kg/m2, were enrolled in the present study and the FTO gene and hsa-miR-150-5p expression, biochemical parameters of blood and anthropometric measurements were analyzed. The results highlight that the FTO gene expression is associated to obesity (p 0.029), LDL-C (p 0.02) and fasting blood glucose (p 0.02), but not with triglycerides (p 0.69), total cholesterol (p 0.21), and HDL-C (p 0.24). The hsa-miR-150-5p is not associated to obesity (p 0.84), triglycerides (p 0.57), total cholesterol (p 0.51), HDL-C (p 0.75), LDL-C (p 0.32), and fasting blood glucose (p 0.42). The FTO gene expression is related to obesity, LDL-C and blood fasting glucose, representing a good molecular marker for obesity.

https://doi.org/10.1590/0001-3765202020200249 566 downloads

12.

MANAGEMENT CLASS DELIMITATION IN A SOYBEAN CROP USING ORBITAL IMAGES
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Zanella, Marco A.

; Queiroz, Daniel M. de

; Valente, Domingos S. M.

; Pinto, Francisco de A. de C.

; Santos, Nerilson T.

Engenharia Agrícola

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Out 2019, Volume 39 Nº 5 Páginas 676 - 683

Resumo: En | Texto: En | PDF: En

ABSTRACT The delimitation of management classes is critical for successful precision agriculture. This process involves choosing the variables to use and analyzing the spatial variability of the variables. Thus, the objective of this study was to analyze the correlation between management class maps generated from orbital images and yield maps. A 95-hectare area of rainfed grain was evaluated. Yield maps were obtained for the 2015/2016 and 2016/2017 soybean crops. Orbital images were used from two dates for each crop to generate vegetation index maps. The spatial correlation between the vegetation indices and the yield maps was obtained using a bivariate Moran index. The delineated management classes were compared using the Kappa index. This study demonstrated that the Kappa values resulting from the comparison between the management class maps generated from the soybean yield and the vegetation index ranged from 5% to 67% depending on the number of delineated classes. The highest Kappa values were observed when the area was delineated into three classes.

https://doi.org/10.1590/1809-4430-eng.agric.v39n5p676-683/2019 519 downloads

13.

INTEGRATION OF A LOW-COST GLOBAL NAVIGATION SATELLITE SYSTEM TO A SINGLE-BOARD COMPUTER USING KALMAN FILTERING
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Silva, Thales M. de A.

; Mayrink, Grégory de O.

; Valente, Domingos S. M.

; Queiroz, Daniel M.

Engenharia Agrícola

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Jun 2019, Volume 39 Nº 3 Páginas 323 - 330

Resumo: En | Texto: En | PDF: En

ABSTRACT The global navigation satellite system (GNSS) is the basis for localized crop management by allowing the georeferencing of collected data and the generation of maps by different systems that compose precision agriculture. There is a demand for low-cost navigation systems to enable their use in agriculture. Therefore, the objective of this study is to integrate a low-cost GNSS module to a single-board computer using Kalman filtering to obtain navigation data. The system was evaluated by performing one static and two kinematic experiments, with three repetitions each. In the static experiment, the mean error was 3.25 m with a root mean square error (RMSE) of 3.73 m. In the first kinematic experiment, data variability was lower at a velocity of 1.39 m s−1. In the second kinematic experiment, the mean error was 1.26 and 1.13 m, and the RMSE was 1.45 and 1.27 m for data obtained before and after filtering, respectively. In conclusion, the system reduces the lateral errors in linear sections but is not indicated for sections that change direction. Moreover, this system can be used in agricultural applications such as soil sampling and crop yield monitoring.

https://doi.org/10.1590/1809-4430-eng.agric.v39n3p323-330/2019 744 downloads

14.

Evaluation of cytogenotoxicity, antioxidant and hypoglycemiant activities of isolate compounds from Mansoa hirsuta D.C. (Bignoniaceae)
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PEREIRA, JOQUEBEDE R.

; QUEIROZ, RAPHAEL F.

; SIQUEIRA, ERLÂNIA A. DE

; BRASILEIRO-VIDAL, ANA CHRISTINA

; SANT’ANA, ANTÔNIO E.G.

; SILVA, DANIEL M.

; AFFONSO, PAULO R.A. DE MELLO

Anais da Academia Brasileira de Ciências

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Mar 2017, Volume 89 Nº 1 Páginas 317 - 331

Resumo: En | Texto: En | PDF: En

ABSTRACT Mansoa hirsuta (Bignoniaceae) is a native plant from caatinga in Brazilian semiarid. This plant has been locally used as antimicrobial and hypoglycemiant agents, but their action mechanisms and toxicity remain largely unknown. Therefore, we evaluated the composition and antioxidant, cytoprotective and hypoglycemiant effects of raw extract, fractions and compounds from leaves of M. hirsuta. The cytogenotoxic effects of ursolic and oleanolic acids, the main phytotherapic components of this plant, were assessed. The raw extract and fractions presented steroids, saponins, flavonols, flavanonols, flavanones, xanthones, phenols, tannins, anthocyanins, anthocyanidins and flavonoids. The ethyl acetate fraction inhibited efficiently the cascade of lipid peroxidation while the hydroalcoholic fraction was richer in total phenols and more efficient in capturing 2,2-diphenyl-1-picrylhydrazyl (·DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS·+) radicals. The isolated fraction of M. hirsuta also inhibited the α-amylase activity. Cytotoxic effects were absent in both raw extract and fractions while ursolic+oleanolic acids were efficient in protecting cells after exposure to hydrogen peroxide. Moreover, this mixture of acid shad no significant interference on the mitotic index and frequency of nuclear and/or chromosomal abnormalities in Allium cepa test. Therefore, M. hirsuta represents a potential source of phytochemicals against inflammatory and oxidative pathologies, including diabetes.

https://doi.org/10.1590/0001-3765201720160585 2322 downloads

15.

Melipona mondury produces a geopropolis with antioxidant, antibacterial and antiproliferative activities
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SANTOS, TÁSSIA L.A. DOS

; QUEIROZ, RAPHAEL F.

; SAWAYA, ALEXANDRA C.H.F.

; LOPEZ, BEGOÑA GIMENEZ-CASSINA

; SOARES, MILENA B.P.

; BEZERRA, DANIEL P.

; RODRIGUES, ANA CAROLINA B.C.

; PAULA, VANDERLÚCIA F. DE

; WALDSCHMIDT, ANA MARIA

Anais da Academia Brasileira de Ciências

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2017, Volume 89 Nº 3 Páginas 2247 - 2259

Resumo: En | Texto: En | PDF: En

ABSTRACT Geopropolis is a special type of propolis produced by stingless bees. Several pharmacological properties have been described for different types of geopropolis, but there have been no previous studies of the geopropolis from Melipona mondury. In this study, we investigated the antioxidant, antibacterial, and antiproliferative activities of M. mondury geopropolis, and determined its chemical profile. The antioxidant activity was determined using in vitro ABTS·+, ·DPPH, and β-carotene/linoleic acid co-oxidation methods. The antibacterial activity was determined using a microdilution method with Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant S. aureus. The antiproliferative effect was determined in tumor cell lines using the Alamar Blue assay. The chemical profile was obtained using UHPLC-MS and UHPLC-MS/MS. The butanolic fraction had the highest concentration of phenolic compounds and more potent antioxidant properties in all assays. This fraction also had bacteriostatic and bactericidal effects against all bacterial strains at low concentrations, especially S. aureus. The hexane fraction had the highest antiproliferative potential, with IC50 values ranging from 24.2 to 46.6 µg/mL in HL-60 (human promyelocytic leukemia cell) and K562 (human chronic myelocytic leukemia cell), respectively. Preliminary chemical analysis indicates the presence of terpenes and gallic acid in the geopropolis. Our results indicate the therapeutic potential of geopropolis from M. mondury against inflammatory, oxidative, infectious, and neoplastic diseases.

https://doi.org/10.1590/0001-3765201720160725 1717 downloads

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