1,481 research outputs found

    Sensibilidade e especificidade dos classificadores de aprendizagem de máquina para o diagnóstico de glaucoma usando Spectral Domain OCT e perimetria automatizada acromática

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    PURPOSE: To evaluate the sensitivity and specificity of machine learning classifiers (MLCs) for glaucoma diagnosis using Spectral Domain OCT (SD-OCT) and standard automated perimetry (SAP). METHODS: Observational cross-sectional study. Sixty two glaucoma patients and 48 healthy individuals were included. All patients underwent a complete ophthalmologic examination, achromatic standard automated perimetry (SAP) and retinal nerve fiber layer (RNFL) imaging with SD-OCT (Cirrus HD-OCT; Carl Zeiss Meditec Inc., Dublin, California). Receiver operating characteristic (ROC) curves were obtained for all SD-OCT parameters and global indices of SAP. Subsequently, the following MLCs were tested using parameters from the SD-OCT and SAP: Bagging (BAG), Naive-Bayes (NB), Multilayer Perceptron (MLP), Radial Basis Function (RBF), Random Forest (RAN), Ensemble Selection (ENS), Classification Tree (CTREE), Ada Boost M1(ADA),Support Vector Machine Linear (SVML) and Support Vector Machine Gaussian (SVMG). Areas under the receiver operating characteristic curves (aROC) obtained for isolated SAP and OCT parameters were compared with MLCs using OCT+SAP data. RESULTS: Combining OCT and SAP data, MLCs' aROCs varied from 0.777(CTREE) to 0.946 (RAN).The best OCT+SAP aROC obtained with RAN (0.946) was significantly larger the best single OCT parameter (p<0.05), but was not significantly different from the aROC obtained with the best single SAP parameter (p=0.19). CONCLUSION: Machine learning classifiers trained on OCT and SAP data can successfully discriminate between healthy and glaucomatous eyes. The combination of OCT and SAP measurements improved the diagnostic accuracy compared with OCT data alone.OBJETIVO: Avaliar a sensibilidade e especificidade dos classificadores de aprendizagem de máquina no diagnóstico de glaucoma usando Spectral Domain OCT (SD-OCT) e perimetria automatizada acromática (PAA). MÉTODOS: Estudo transversal observacional. Sessenta e dois pacientes com glaucoma e 48 indivíduos normais foram incluídos. Todos os pacientes foram submetidos a exame oftalmológico completo, e perimetria automatizada acromática (24-2 SITA; Humphrey Field Analyzer II, Carl Zeiss Meditec, Inc., Dublin, CA) e exame de imagem da camada de fibras nervosas utilizando SD-OCT (Cirrus HD-OCT; Carl Zeiss Meditec Inc., Dublin, California). Curvas ROC (Receiver operator characteristic) foram obtidas para todos os parâmetros do SD-OCT e índices globais do campo visual (MD, PSD, GHT). Subsequentemente, os seguintes classificadores de aprendizagem de máquina (CAMs) foram testados usando parâmetros do OCT e CV: Bagging (BAG), Naive-Bayes (NB), Multilayer Perceptron (MLP), Radial Basis Function (RBF), Random Forest (RAN), Ensemble Selection (ENS), Classification Tree (CTREE), Ada Boost M1(ADA), Support Vector Machine Linear (SVML) e Support Vector Machine Gaussian (SVMG). Áreas abaixo da curva ROC (aROC) obtidas com os parâmetros isolados do campo visual (CV) e OCT foram comparados com os CAMs usando dados associados do OCT e CV. RESULTADOS: Combinando os dados do OCT e do CV, aROCs dos CAMs variaram entre 0,777(CTREE) e 0,946 (RAN). A maior aROC dos CAMs OCT+CV obtida com RAN (0,946) foi significativamente maior que o melhor parâmetro do OCT (p<0,05), mas não houve diferença estatística significativa com o melhor parâmetro do CV (p=0,19). CONCLUSÃO: Os classificadores de aprendizagem de máquina treinados com dados do OCT e CV podem discriminar entre olhos normais e glaucomatosos com sucesso. A combinação das medidas do OCT e CV melhoraram a acurácia diagnóstica comparados aos parâmetros do OCT.17017

    Sensitivity And Specificity Of Machine Learning Classifiers For Glaucoma Diagnosis Using Spectral Domain Oct And Standard Automated Perimetry.

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    To evaluate the sensitivity and specificity of machine learning classifiers (MLCs) for glaucoma diagnosis using Spectral Domain OCT (SD-OCT) and standard automated perimetry (SAP). Observational cross-sectional study. Sixty two glaucoma patients and 48 healthy individuals were included. All patients underwent a complete ophthalmologic examination, achromatic standard automated perimetry (SAP) and retinal nerve fiber layer (RNFL) imaging with SD-OCT (Cirrus HD-OCT; Carl Zeiss Meditec Inc., Dublin, California). Receiver operating characteristic (ROC) curves were obtained for all SD-OCT parameters and global indices of SAP. Subsequently, the following MLCs were tested using parameters from the SD-OCT and SAP: Bagging (BAG), Naive-Bayes (NB), Multilayer Perceptron (MLP), Radial Basis Function (RBF), Random Forest (RAN), Ensemble Selection (ENS), Classification Tree (CTREE), Ada Boost M1(ADA),Support Vector Machine Linear (SVML) and Support Vector Machine Gaussian (SVMG). Areas under the receiver operating characteristic curves (aROC) obtained for isolated SAP and OCT parameters were compared with MLCs using OCT+SAP data. Combining OCT and SAP data, MLCs' aROCs varied from 0.777(CTREE) to 0.946 (RAN).The best OCT+SAP aROC obtained with RAN (0.946) was significantly larger the best single OCT parameter (p<0.05), but was not significantly different from the aROC obtained with the best single SAP parameter (p=0.19). Machine learning classifiers trained on OCT and SAP data can successfully discriminate between healthy and glaucomatous eyes. The combination of OCT and SAP measurements improved the diagnostic accuracy compared with OCT data alone.76170-

    Nonlinear optimization for human-like synchronous movements of a dual arm-hand robotic system

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    In previous work we have presented a model capable of generating human-like movements for a dual arm-hand robot involved in human-robot cooperative tasks. However, the focus was on the generation of reach-to-grasp and reach-to-regrasp bimanual movements and no synchrony in timing was taken into account. In this paper we extend the previous model in order to accomplish bimanual manipulation tasks by synchronously moving both arms and hands of an anthropomorphic robotic system. Specifically, the new extended model has been designed for two different tasks with different degrees of difficulty. Numerical results were obtained by the implementation of the IPOPT solver embedded in our MATLAB simulator

    Performance and modeling of Ni(II) adsorption from low concentrated wastewater on carbon microspheres prepared from tangerine peels by FeCl3-assisted hydrothermal carbonization

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    The presence of heavy metals in the environment as a consequence of human activity is an issue that has caught the attention of researchers to find wastewater treatment solutions, such as adsorption. In this work, hydrochars and activated carbon microspheres are prepared from tangerine peels as carbon precursor and FeCl3 as activating and structure-directing agent in the hydrothermal carbonization, allowing to obtain hydrochar microspheres ranging from 50 to 3615 nm. In addition, a pyrochar was prepared by pyrolysis of the same precursor. The activated carbon shows the highest surface area (SBET up to 287 m2 g–1), but the basicity of the pyrochar (1.83 mmol g 1, SBET = 104 m2 g–1) was determinant in the adsorption of Ni, being considered the carbon-based material with the highest uptake capacity of Ni. Isotherm and kinetic adsorption of Ni on the most representative activated carbon microsphere, pyrochar and hydrochar microsphere are assessed by 10 and 7 models, respectively.The authors are grateful to the FCT (Foundation for Science and Technology, Portugal) and FEDER (European Regional Development Fund) under Programme PT2020 for financial support to CIMO (UIDB/00690/2020). We would also like to thank the scientific collaboration under Base- UIDB/50020/2020 and Programmatic- UIDP/50020/2020 funding of LSRE-LCM, and LA/P/0045/2020 funding of ALiCE, funded by national funds through FCT and MCTES (Ministério da Ciência, Tecnologia e Ensino Superior, Portugal) by PIDDAC (Programa de Investimentos e Despesas de Desenvolvimento da Administraç˜ao Central, Portugal). Fernanda F. Roman and Adriano dos Santos Silva acknowledge the national funding by FCT and MIT (Massachusetts Institute of Technology, USA), and the ESF (European Social Fund) for individual research grants with reference numbers of SFRH/BD/143224/2019 and SFRH/BD/151346/2021, respectively.info:eu-repo/semantics/publishedVersio

    <i>Aspergillus labruscus</i> sp. nov., a new species of <i>Aspergillus</i> section <i>Nigri</i> discovered in Brazil

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    AbstractA novel fungal species, Aspergillus labruscus sp. nov., has been found in Brazil during an investigation of the fungal species present on the surface of grape berries (Vitis labrusca L.) for use in the production of concentrated grape juice. It seems to be associated to V. labrusca, and has never been recovered from Vitis vinifera. This new species belonging to Aspergillus subgenus Circumdati section Nigri is described here using morphological characters, extrolite profiling, partial sequence data from the BenA and CaM genes, and internal transcribed spacer sequences of ribosomal DNA. Phenotypic and molecular data enabled this novel species to be clearly distinguished from other black aspergilli. A. labruscus sp. nov. is uniseriate, has yellow mycelium, poor sporulation on CYA at 25 °C, abundant salmon to pink sclerotia and rough conidia. Neoxaline and secalonic acid D were consistently produced by isolates in this taxon. The type strain of A. labruscus sp. nov. is CCT 7800 (T) = ITAL 22.223 (T) = IBT 33586 (T).</jats:p

    Tuning the Biological Activity of Camphorimine Complexes through Metal Selection

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    This research was funded by FCT—Fundação para a Ciência e a Tecnologia, through projects CQE (UIDB/00100/2020 and UIDP/00100/2020) and C2TN (UID/MULTI/04349/2019), the projects of the Research Unit Institute for Bioengineering and Biosciences—iBB (UIDB/04565/2020 and UIDP/04565/2020), the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB, and a PhD grant to J.P.C. (UI/BD/152244/2021).The cytotoxic activity of four sets of camphorimine complexes based on the Cu(I), Cu(II), Ag(I), and Au(I) metal sites were assessed against the cisplatin-sensitive A2780 and OVCAR3 ovarian cancer cells. The results showed that the gold complexes were ca. one order of magnitude more active than the silver complexes, which in turn were ca. one order of magnitude more active than the copper complexes. An important finding was that the cytotoxic activity of the Ag(I) and Au(I) camphorimine complexes was higher than that of cisplatin. Another relevant aspect was that the camphorimine complexes did not interact significantly with DNA, in contrast with cisplatin. The cytotoxic activity of the camphorimine complexes displayed a direct relationship with the cellular uptake by OVCAR3 cells, as ascertained by PIXE (particle-induced X-ray emission). The levels of ROS (reactive oxygen species) formation exhibited an inverse relationship with the reduction potentials for the complexes with the same metal, as assessed by cyclic voltammetry. In order to gain insight into the toxicity of the complexes, their cytotoxicity toward nontumoral cells (HDF and V79 fibroblasts) was evaluated. The in vivo cytotoxicity of complex 5 using the nematode Caenorhabditis elegans was also assessed. The silver camphorimine complexes displayed the highest selectivity coefficients (activity vs. toxicity).publishersversionpublishe

    Monitoring of outdoor tourism demand

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    The Herfindahl-Hirschman Index (HHI) was used in order to understand the tourism competitiveness of the different sub-regions that make up the North Region of Portugal. This index is a measure which helps to analyse market concentration and at the same time determines the competitiveness of the market.Project “TURNOUT: Desenvolvimento do Turismo Outdoor da Região Norte de Portugal”, with the reference POCI-01-0145-FEDER-032289 and funded by the European Regional Development Fund (FEDER). This work is, also, funded by National Funds through the Foundation for Science and Technology under the project UIDB/04752/2020.info:eu-repo/semantics/publishedVersio

    Comparison of cadmium binding by humic and fulvic acids extracted from two composts of different origin

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    Composting has been proven to be an environmentally friendly process for urban organic waste, that can represent an opportunity for new uses under the circular economy framework. The binding of cadmium to fulvic-like and humic-like acids extracted from compost of algae and urban residues were evaluated, and the results show significant differences. The fulvic and humic acids from algae compost bind cadmium more efficiently than those from urban residues compost. Furthermore, data from humic acids from both composts display significantly higher ability to bind to cadmium than both their corresponding fulvic acids and the generic soil extracted humic matter.  Cooperation Program Interreg V-A Spain-Portugal (POCTEP) 2014-2020 and the European Union through the European Regional Development Fund -FEDER within the scope of the project «RES2VALHUM -Valorization of Organic Waste: Production of Humic Substances» (0366_RES2VALHUM_1_P).The authors want to thank LIPOR for the supply of COUR sample. Members of the USC are also grateful to CRETUS Strategic Partnership (ED431E 2018/01) co-funded by FEDER and the Galician Competitive Research Group GRC ED431C/12.Members of the Department of Chemistry are also grateful toCenter of Chemistrythrough projects UID/QUI/00686/2016 and UID/QUI/00686/2019 (CQUM) funded by Foundation for Science and Technology (FCT, Portugal

    Comparison of cadmium binding by humic and fulvic acids extracted from compost samples of different feedstock

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    Compost is a bio-sustainable material produced by the controlled decomposition of the organic wastes. Composting can be employed for the urban organic waste treatment in alternative to incineration or landfill disposal [1]. The properties of compost are closely related to the presence of humic-like substances (HS). Both fulvic acids (FA) and humic acids (HA) contain a significant amount of carboxylic acids and phenolic groups that are responsible for some of their properties like solubility and ability to complex metal ions [2]. In the scope of the project Res2ValHum [3], composts produced from different feedstock were analysed and compared regarding the ability of the FA and the HA extracts to bind Cd2+. The free cadmium ion concentration was measured using the electroanalytical technique AGNES (absence of gradients and Nernstian equilibrium stripping) [4]. The cadmium binding by FA and HA extracts of two compost samples: compost of algae (CA) and compost of sludge sewage (CSS) is illustrated in Figure 1. Results indicate that the extent of the binding of cadmium by FA is similar despite the nature of the compost. In opposition, the HA extracts from the algae compost exhibit a larger capacity to bind cadmium ion in comparison to the extracted from the sludge sewage compost. These results indicate that the nature of the feedstock seem to affect more the structure of the HA (in comparison to the FA) formed during the composting process. The chemical characterization of these extracts by different analytical techniques are in course in order to fully understand the referred effect.0366_RES2VALHUM_1_P - Valorização de resíduos orgânicos: produção de substâncias húmicas, cofinanciada pelo Fundo Europeu de Desenvolvimento regional (FEDER) através do Programa INTERREG V-A Espanha-Portugal (POCTEP) 2014-202
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