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Automatic Detection of COVID-19 Infection Using Chest X-Ray Images Through Transfer Learning

IEEE/CAA Journal of Automatica Sinica 2021年第1期8卷 239-248页

作者： Elene Firmeza Ohata gabriel maia bezerra João Victor Souza das Chagas Aloísio Vieira Lira Neto Adriano Bessa Albuquerque Victor Hugo Cde Albuquerque Pedro Pedrosa Rebouças Filho the Universidade Federal do Ceará FortalezaCE 60455-970and also with the Instituto Federal do CearáFortalezaCE 60040-215Brazil the Instituto Federal do Ceará FortalezaCE 60040-215Brazil the Universidade de Fortaleza FortalezaCE 60811-905Brazil

The new coronavirus(COVID-19),declared by the World Health Organization as a pandemic,has infected more than 1 million people and killed more than 50 *** infection caused by COVID-19 can develop into pneumonia,which can be detected by a chest X-ray exam and should be treated *** this work,we propose an automatic detection method for COVID-19 infection based on chest X-ray *** datasets constructed for this study are composed of194 X-ray images of patients diagnosed with coronavirus and 194 X-ray images of healthy *** few images of patients with COVID-19 are publicly available,we apply the concept of transfer learning for this *** use different architectures of convolutional neural networks(CNNs)trained on Image Net,and adapt them to behave as feature extractors for the X-ray ***,the CNNs are combined with consolidated machine learning methods,such as k-Nearest Neighbor,Bayes,Random Forest,multilayer perceptron(MLP),and support vector machine(SVM).The results show that,for one of the datasets,the extractor-classifier pair with the best performance is the Mobile Net architecture with the SVM classifier using a linear kernel,which achieves an accuracy and an F1-score of 98.5%.For the other dataset,the best pair is Dense Net201 with MLP,achieving an accuracy and an F1-score of 95.6%.Thus,the proposed approach demonstrates efficiency in detecting COVID-19 in X-ray images.

关键词： Convolutional neural networks(CNNs) COVID-19 transfer learning X-ray

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Enhancement of the Antigenotoxic and Antioxidant Actions of Eugenol from Spice Clove and the Stabilizer Gum Arabic on Colorectal Carcinogenesis

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Food and Nutrition Sciences 2024年第1期15卷 71-100页

作者： Nayanna de Oliveira Ramos Melo Lucas gabriel da Costa Marques Humberto maia Costa Neto Matheus De Sousa Silva Francisco Vagnaldo Fechine Jamacaru Bruno Coêlho Cavalcanti Antônio Adailson De Sousa Silva Conceição Aparecida Dornelas Postgraduate Program in Medical-Surgical Sciences School of Medicine Federal University of Ceará Fortaleza Brazil School of Medicine Federal University of Ceará Fortaleza Brazil Nucleus of Research and Development of Medicines (NPDM) Laboratory of Pharmacology and Preclinical Research School of Medicine Federal University of Ceará Fortaleza Brazil Nucleus for Research and Development of Medicines (NPDM) National Laboratory of Experimental Oncology Federal University of Ceará Fortaleza Brazil Postgraduate Program in Pathology and Medical-Surgical Sciences School of Medicine Federal University of Ceará Fortaleza Brazil

Spices are defined as any aromatic condiment of plant origin used to alter the flavor and aroma of foods. Besides flavor and aroma, many spices have antioxidant activity, mainly related to the presence in cloves of phenolic compounds, such as flavonoids, terpenoids and eugenol. In turn, the most common uses of gum arabic are in the form of powder for addition to soft drink syrups, cuisine and baked goods, specifically to stabilize the texture of products, increase the viscosity of liquids and promote the leavening of baked products (e.g., cakes). Both eugenol, extracted from cloves, and gum arabic, extracted from the hardened sap of two species of the Acacia tree, are dietary constituents routinely consumed virtually throughout the world. Both of them are also widely used medicinally to inhibit oxidative stress and genotoxicity. The prevention arm of the study included groups: Ia, IIa, IIIa, Iva, V, VI, VII, VIII. Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the same period and for an additional 9 weeks, the animals received either water, 10% GA, EUG, or 10% GA + EUG by gavage. The treatment arm of the study included groups Ib, IIb, IIIb e IVb, IX, X, XI, XII). Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the subsequent 9 weeks, the animals received either water, 10% GA, EUG or 10% GA + EUG by gavage. The novelty of this study is the investigation of their use alone and together for the prevention and treatment of experimental colorectal carcinogenesis induced by dimethylhydrazine. Our results show that the combined use of 10% gum arabic and eugenol was effective, with antioxidant action in the colon, as well as reducing oxidative stress in all colon segments and preventing and treating genotoxicity in all colon segments. Furthermore, their joint administration reduced the number of aberrant crypts and th

关键词： Eugenol Gum Arabic Carcinogenesis Oxidative Stress Genotoxicity

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Novel experimental techniques to assess the time-dependent deformations of geosynthetics under soil confinement

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 410-419页

作者： Carina maia Lins Costa Jorge gabriel Zornberg Department of Civil Engineering Federal University of Rio Grande do NorteAv.Senador Salgado Filho 3000NatalRio Grande do Norte59078-970Brazil Department of Civil Architectural and Environmental Engineering The University of Texas at Austin301 E.Dean KeetonAustinTX78712-0280USA

A new experimental approach to assess the impact of soil confinement on the long-term behavior of geosynthetics is presented in this *** experimental technique described herein includes a novel laboratory apparatus and the use of different types of tests that allow generation of experimental data suitable for evaluation of the time-dependent behavior of geosynthetics under soil *** soil-geosynthetic interaction equipment involves a rigid box capable of accommodating a cubic soil mass under plane strain conditions.A geosynthetic specimen placed horizontally at the mid-height of the soil mass is subjected to sustained vertical pressures that,in turn,induce reinforcement axial loads applied from the soil to the *** previously reported studies on geosynthetic behavior under soil confinement,the equipment was found to be particularly *** minor setup modifications,not only interaction tests but also in-isolation geosynthetic stress relaxation tests and soil-only tests under a constant strain rate can be conducted using the same ***,the time histories of the reinforcement loads and corresponding strains are generated throughout the *** from typical tests conducted using sand and a polypropylene woven geotextile are presented to illustrate the proposed experimental *** testing procedure was found to provide adequate measurements during tests,including good repeatability of test *** soilegeosynthetic interaction tests were found to lead to increasing geotextile strains with time and decreasing reinforcement tension with *** test results highlighted the importance of measuring not only the time history of displacements but also that of reinforcement loads during *** approach of using different types of tests to analyze the soilegeosynthetic interaction behavior is an innovation that provides relevant insight into the impact of soil confinement on the time-dependent deformations of geos

关键词： Geosynthetics Geotextile Creep Stress relaxation Reinforced soil Long-term deformation

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Qualification and validation test methodology of the open-source CubeSat FloripaSat-I

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1230-1244页

作者： MARCELINO gabriel Mariano FILHO Edemar Morsch MARTINEZ Sara Vega DE MATTOS AndréMartins Pio SEMAN Laio Oriel SLONGO Leonardo Kessler bezerra Eduardo Augusto Department of Electrical Engineering Federal University of Santa CatarinaFlorianópolis 88040-900Brazil SENAI Institute of Innovation in Embedded Systems Florianópolis 88054-700Brazil School of Sea Science and TechnologyUniversity of Vale do ItajaíItajaí88302-901Brazil

The FloripaSat-I project consists of an initiative from the Federal University of Santa Catarina(UFSC),in Brazil,to train students to design,test and integrate innovative space *** group just developed its first open-source CubeSat,the FloripaSat-I,which aims to empower students to develop space systems through a practical approach,where they have full control of the design and test of a real *** project has already gone through all the stages of a CubeSat mission prior to the launching and operation stages.A prototype of the satellite,as well the engineering models 1 and 2(EM-I and EM-II)were *** expertise provided by the engineering models allows the development of a functional flight model(FM).This paper presents the validation and qualification tests that pass various FloripaSat-I models,from the engineering model to the flight *** stages of the project are described,the tests performed in each phase,as well as the lessons ***,this paper serves as a guidance for other university teams that want to test their own CubeSats,as well as teams that want to use the open-source hardware and software left as heritage by this project.

关键词： embedded system nanosatellite cubesats test methodology

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Gripper Design for Radio Base Station Autonomous Maintenance System

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International Journal of Automation and computing 2021年第4期18卷 645-653页

作者： gabriel Reis Marrone Dantas Daniel bezerra Gibson Nunes Pedro Dreyer Carolina Ledebour Judith Kelner Djamel Sadok Ricardo Souza Silvia Lins Maria Marquezini Networking and Telecommunications Research Group Informatics CenterFederal University of PernambucoRecife 50730-120Brazil Ericsson Research Indaiatuba 13337-300Brazil

For an autonomous system to perform maintenance tasks in a networking device or a radio base station(RBS), it has to deal with a series of technological challenges ranging from identifying hardware-related problems to manipulating connectors. This paper describes the development of a robot maintenance system dedicated to detect and resolve faulty links caused by unplugged or poorly connected cables. Although the maintenance system relies on four subsystems, we significantly focus on our low-cost and efficient custom gripper solution developed to handle RJ45 Ethernet connectors. To examine our gripper, we conducted three experiments. First, a qualitative questionnaire was submitted to 30 users in the case of the teleoperated scenario of the gripper attached to a robotic arm. Similarly, we also tested the automatic operation mode. The results showed that our system is reliable and delivers a highly efficient maintenance tool in both teleoperated and autonomous operation modes. The practical experiment containing the removal or unplugging of connectors demonstrated our gripper′s ability to adequately handle these, whereas the feedback from the questionnaire pointed to a positive user experience. The automatic test assessed the gripper′s robustness against the continuous operation.

关键词： Robotic gripper maintenance system gripper design 3D print product development

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Optimizing power oscillations in an ellipsometric system

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Chinese Optics Letters 2018年第3期16卷 48-52页

作者： Manoel P. Araújo Stefano De Leo gabriel G. maia Institute of Physics Cleb Wataghin State University of Campinas Campinas 13083-872 Brazil Department of Applied Mathematics State University of Campinas Campinas 13083-250 Brazil

Ellipsometry is a powerful and well-established optical technique used in the characterization of materials. It works by combining the components of elliptically polarized light in order to draw information about the optical system. We propose an ellipsometric experimental set-up to study polarization interference in the total internal reflection regime for Gaussian laser beams. The relative phase between orthogonal states can be measured as a power oscillation of the optical beam transmitted through a dielectric block, and the orthogonal components are then mixed by a polarizer. We show under which conditions the plane wave analysis is valid, and when the power oscillation can be optimized to reproduce a full pattern of oscillation and to simulate quarter- and half-wave plates.

关键词： Optimizing power oscillations in an ellipsometric system

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Physiological plasticity in eucalyptus clones in the vegetative stage contributes to drought tolerance

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林业研究:英文版 2023年第5期34卷 1549-1561页

作者： Vilma Marques Ferreira Jailma Ribeiro de Andrade Claudiana Moura dos Santos Sebastiao de Oliveira maia Júnior Joao Correia de Araújo Neto Andrea Francisca da Silva Santos Vicente Mota da Silva Lucas Teles bezerra Laurício Endres Laboratório de Fisiologia Vegetal Campus de Engenharia e Ciências AgráriasUniversidade Federal de AlagoasRio LargoAL57072-900Brazil Laboratório de Ciências Ambientais e Biodiversidade Departamento de Zootecnia.Centro de Ciências AgráriasUniversidade Estadual do MaranhãoSão LuísMA65300-000Brazil Laboratório de Propagação de Plantas.Campus de Engenharia e Ciências Agrárias Universidade Federal de AlagoasRio LargoAL57072-900Brazil Laboratório de Lepidoptera Museu de ZoologiaUniversidade de São PauloIpirangaSão PauloSP04263-000Brazil

With the expansion of eucalyptus crops to areas with severe water limitations,physiological studies involving eucalyptus clones to identify those that are tolerant to water stress become *** objective of this study was to assess morphological and physiological responses by eucalyptus clones subjected to drought stress and *** experiment consisted of three eucalyptus clones:VC865,I224 and I144 and two water regimes:control and water stress followed by rehydration,with six *** water potential,gas exchange,maximum quantum efficiency of photo systemⅡand plant height and stem diameter were evaluated under drought stress and ***6 d of rehydration,the number of leaves,leaf area and dry mass of root,leaf,stem and their total were *** clones showed intense reduction of gas exchange during the drought stress period,and only VC865 and 1144 showed rapid recovery with 3 d of *** 1224 showed greater reduction in height,stem diameter,number of leaves,water potential at midday(Ψ_(w)_(Midday)),and maximum quantum efficiency of photosystemⅡ(F_(v)/F_(m)).Clones VC865and T144 showed lower reductions inΨ_(wMidday)and F_(v)/F_(m) under ***865 had lower reductions in leaf number,leaf area and higher leaf dry mass,while clone I144 had higher height and lower reduction in root dry mass *** these clones showed higher water use efficiency with 3d of *** different phenotypic plasticities gave the clones VC865 and 1144 efficient mechanisms of acclimatization to stress and more drought tolerance,enhancing their greater capacity for recovery after stress,which allowed lower dry mass *** 1224,however,was more susceptible to drought stress,undergoing greater physiological damage with only partial recovery during rehydration.

关键词： Drought Eucalyptus species Gas exchanges Post-stress Root dry mass

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Productivity and Water-Use Efficiency of Sorghum in Rainfed Regime in the Semi-Arid Region of Brazil

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American Journal of Plant Sciences 2017年第9期8卷 2133-2148页

作者： Erialdo de Oliveira Feitosa Antonio Flávio Batista Araújo Calorine Maria Bayma Oliveira Fernando bezerra Lopes Eunice maia de Andrade Department Agricultural Engineering Federal University of Ceará Campus of Pici Fortaleza Brazil

Sorghum has become ever more prominent on the global energy scene, with studies in the area becoming extremely important. Agricultural production in the semi-arid region of the Brazilian Northeast is intrinsically dependent on rainfall in the region. However, on both inter- and intra-annual scales, the rainfall regime is quite irregular. The aim of this study was to evaluate the productivity of sorghum grown under a rainfed regime, and the water-use efficiency of crops in the semi-arid region of the northeast of Brazil. The work was carried out in the city of Tabuleiro do Norte in the semi-arid region of the State of Ceará. Mean productivity of the sorghum was 919.42 kg·ha-1, with maximum values being recorded for lot 02 (1032 kg·ha-1), lot 03 (1102 kg·ha-1), lot 04 (2143 kg·ha-1) and lot 12 (1367 kg·ha-1). The greatest value for water-use efficiency, 1.13 m3·kg-1, was found for lot 04, while the smallest value, 4.83 m3·kg-1 was seen in lot 02. It was found that the low productivity of sorghum in a rainfed regime shows that the lack of success in production systems in semi-arid regions is not due to the total amount of rainfall, but rather the spatial and temporal distribution of the rains, as well as the occurrence of hot, dry spells. Furthermore, it can be seen that the best ratio of grain production to water demand shows a strong correlation with the distribution of water throughout the cycle, and not only with the total volume.

关键词： Production Rainfed Agriculture Sorghum bicolor L.

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Determining the Soil Erodibility for an Experimental Basin in the Semi-Arid Region Using Geoprocessing

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American Journal of Plant Sciences 2017年第12期8卷 3174-3188页

作者： Erich Celestino Braga Pereira Fernando bezerra Lopes Francisco Emanoel Firmino Gomes Aldenia Mendes Masceno de Almeida Ana Caroline Messias de Magalhaes Eunice maia de Andrade Department Agricultural Engineering Federal University of CearáFortalezaBrazil Department of Soil Science Federal University of CearáFortalezaBrazil

Erosion is the natural process which has the greatest environmental impact, and is the principal trigger for desertification around the globe. The main model used to estimate soil loss by erosion is the Universal Soil Loss Equation (USLE), which unites the major factors that influence erosion into one equation. The soil erodibility factor (K) is the component of this equation that represents soil physics, and is defined as the inherent capacity of the soil to withstand disintegration of its particles and their subsequent transport. The use of geostatistics is seen as an alternative in spatializing this variable from sampled to non-sampled points. The aim of this study therefore, was to determine the soil erodibility factor for an experimental basin in the semi-arid region of Brazil, in addition to generating the soil erodibility map using geostatistics. Disturbed and undisturbed soil samples were collected from 35 points, and laboratory samples were processed to determine the granulometry, permeability and organic matter of the soil, data which are used to determine the K-factor. Kriging was performed to spatialize the study variable, when spherical, exponential and Gaussian semivariograms were tested for generation of the soil erodibility map, these being evaluated by their respective deviations resulting from cross-validation. The mean value of K for the Haplic Luvisol was 0.0328 ton·ha·h/ha·MJ·mm;for the eutrophic Red-Yellow Argisol it was 0.0258 ton·ha·h/ha·MJ·mm;and for the Fluvic Neosol, it was 0.0424 ton·ha·h/ha·MJ·mm. The experimental basin is classified as highly erodible. The semivariogram that presented the best fit for generating the soil erodibility map of the study area was Gaussian.

关键词： Erosion Universal Soil Loss Equation Geostatistics

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Production of Aflatoxins from Aspergillus flavus in Liquid Medium

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Journal of Life Sciences 2013年第4期7卷 377-381页

作者： Maria Edite bezerra da Rocha Francisco das Chagas Oliveira Freire Icaro Gusmao Pinto Vieira Jose Mariados Santos Filho Fabio Erlan Feitosa maia Maria Izabel Florindo Guedes Davide Rondina Universidade Estadual do Ceara Avenida Paranjana 1700 CEP: 60740-000 Fortaleza Ceara Brasil Embrapa Agroindustria Tropical Rua Dra. Sara Mesquita 2270 CEP: 60.511-110 Fortaleza-CE Brasil

Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus, and can be found in many grains such as peanuts, soybeans and com. This study aimed to qualitatively and quantitatively evaluate the production of aflatoxin in liquid media using strains of Aspergillus flavus obtained from peanuts marketed in the city of Fortaleza, CEo Strains of Aspergillus flavus were inoculated into a liquid medium malt extract and after 2 days inoculated into a second medium containing sucrose 5%, MgSO4·7H20 0.1%, KH2PO4 1%, ZnSO4·7H2O 0.0176 g, and cultured for 3 more days. The media were kept at room temperature ranging from 24°C to 32 °C with agitation of 130 rpm and aeration of 4.17 Llmin. Qualitative analysis was performed by thin layer chromatography and quantitatively by high performance liquid chromatography with fluorescence detection, demonstrating the production of aflatoxin B I （588 mg/L） and B2 （929 mg/L）.

关键词： Peanut fungi micotoxins chromatography.

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