48 research outputs found

    Synthesis of titanate nanofibers co-sensitized with ZnS and Bi2S3 nanocrystallites and their application on pollutants removal

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    The synthesis of nanocomposite materials combining titanate nanofibers (TNF) with nanocrystalline ZnS and Bi2S3 semiconductors is described in this work. The TNF were produced via hydrothermal synthesis and sensitized with the semiconductor nanoparticles, through a single-source precursor decomposition method. ZnS and Bi2S3 nanoparticles were successfully grown onto the TNF's surface and Bi2S3-ZnS/TNF nanocomposite materials with different layouts were obtained using either a layer-by-layer or a co-sensitization approach. The samples' photocatalytic performance was first evaluated through the production of the hydroxyl radical using terephthalic acid as probe molecule. All the tested samples show photocatalytic ability for the production of this oxidizing species. Afterwards, the samples were investigated for the removal of methylene blue. The nanocomposite materials with best adsorption ability for the organic dye were the ZnS/TNF and Bi2S3ZnS/TNF. The removal of the methylene blue was systematically studied, and the most promising results were obtained considering a sequential combination of an adsorption-photocatalytic degradation process using the Bi2S3ZnS/TNF powder as a highly adsorbent and photocatalyst material.Comment: 26 pages, 10 figure

    Conservation units in the core area of the Cerrado domain: an overview on the small nonvolant mammals (Rodentia and Didelphimorphia)

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    A review of small non-volant mammal species of the APA Gama e Cabeça de Veado was carried out, including new surveys in the "Estação Ecológica do Jardim Botânico" (EEJBB) and "Reserva Ecológica do Instituto Brasileiro de Geografia e Estatí­stica" (REIBGE). Thirty-one small mammal's species are registered for the APA Gama and Cabeça de Veado, including one exotic species. Didelphis albiventris, Hylaeamys megacephalus, and Oxymycterus delator were collected for the first time in EEJBB. The APA Gama-Cabeça de Veado has a central position in the Cerrado domain sharing six species with the Amazon domain, five with Atlantic Forest, and 13 with Caatinga. The APA Gama-Cabeça de Veado encompasses the home range of at least six non-volant small mammal species endemic of Cerrado domain, and it has an important role in the protection of these endemic species and species that occurs in those four South America morphoclimatic domains

    Extracellular volume-guided late gadolinium enhancement analysis for non-ischemic cardiomyopathy: The Women's Interagency HIV Study

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    Background Quantification of non-ischemic myocardial scar remains a challenge due to the patchy diffuse nature of fibrosis. Extracellular volume (ECV) to guide late gadolinium enhancement (LGE) analysis may achieve a robust scar assessment. Methods Three cohorts of 80 non-ischemic-training, 20 non-ischemic-validation, and 10 ischemic-validation were prospectively enrolled and underwent 3.0 Tesla cardiac MRI. An ECV cutoff to differentiate LGE scar from non-scar was identified in the training cohort from the receiver-operating characteristic curve analysis, by comparing the ECV value against the visually-determined presence/absence of the LGE scar at the highest signal intensity (SI) area of the mid-left ventricle (LV) LGE. Based on the ECV cutoff, an LGE semi-automatic threshold of n-times of standard-deviation (n-SD) above the remote-myocardium SI was optimized in the individual cases ensuring correspondence between LGE and ECV images. The inter-method agreement of scar amount in comparison with manual (for non-ischemic) or full-width half-maximum (FWHM, for ischemic) was assessed. Intra- and inter-observer reproducibility were investigated in a randomly chosen subset of 40 non-ischemic and 10 ischemic cases. Results The non-ischemic groups were all female with the HIV positive rate of 73.8% (training) and 80% (validation). The ischemic group was all male with reduced LV function. An ECV cutoff of 31.5% achieved optimum performance (sensitivity: 90%, specificity: 86.7% in training; sensitivity: 100%, specificity: 81.8% in validation dataset). The identified n-SD threshold varied widely (range 3 SD-18 SD), and was independent of scar amount (beta = -0.01, p = 0.92). In the non-ischemic cohorts, results suggested that the manual LGE assessment overestimated scar (%) in comparison to ECV-guided analysis [training: 4.5 (3.2-6.4) vs. 0.92 (0.1-2.1); validation: 2.5 (1.2-3.7) vs. 0.2 (0-1.6); P < 0.01 for both]. Intra- and inter-observer analyses of global scar (%) showed higher reproducibility in ECV-guided than manual analysis with CCC = 0.94 and 0.78 versus CCC = 0.86 and 0.73, respectively (P < 0.01 for all). In ischemic validation, the ECV-guided LGE analysis showed a comparable scar amount and reproducibility with the FWHM. Conclusions ECV-guided LGE analysis is a robust scar quantification method for a non-ischemic cohort. Trial registration ClinicalTrials.gov; NCT00000797, retrospectively-registered 2 November 1999; NCT02501811, registered 15 July 2015.Cardiovascular Aspects of Radiolog

    Conservation units in the core area of the Cerrado domain: an overview on the small nonvolant mammals (Rodentia and Didelphimorphia)

    Get PDF
    A review of small non-volant mammal species of the APA Gama e Cabeça de Veado was carried out, including new surveys in the "Estação Ecológica do Jardim Botânico" (EEJBB) and "Reserva Ecológica do Instituto Brasileiro de Geografia e Estatí­stica" (REIBGE). Thirty-one small mammal's species are registered for the APA Gama and Cabeça de Veado, including one exotic species. Didelphis albiventris, Hylaeamys megacephalus, and Oxymycterus delator were collected for the first time in EEJBB. The APA Gama-Cabeça de Veado has a central position in the Cerrado domain sharing six species with the Amazon domain, five with Atlantic Forest, and 13 with Caatinga. The APA Gama-Cabeça de Veado encompasses the home range of at least six non-volant small mammal species endemic of Cerrado domain, and it has an important role in the protection of these endemic species and species that occurs in those four South America morphoclimatic domains
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