9 research outputs found

    Three-Dimensional and Biomimetic Technology in Cardiac Injury After Myocardial Infarction: Effect of Acellular Devices on Ventricular Function and Cardiac Remodelling

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    Dilated cardiomyopathy (DMC) of ischemic or non-ischemic aetiology remains a lethal condition nowadays. Despite early percutaneous or medical revascularization after an acute myocardial infarct (AMI), many patients still develop DMC and severe heart failure due to cardiac remodelling. Possibility of regenerating myocardium already damaged or at least inducing a more positive cardiac remodelling with use of biodegradable scaffolds has been attempted in many experimental studies, which can be cellular or acellular. In the cellular scaffolds, the cells are incorporated in the structure prior to implantation of the same into the injured tissue. Acellular scaffolds, in turn, are composites that use one or more biomaterials present in the extracellular matrix (ECM), such as proteoglycans non-proteoglycan polysaccharide, proteins and glycoproteins to stimulate the chemotaxis of cellular/molecular complexes as growth factors to initiate specific regeneration. For the development of scaffold, the choice of biomaterials to be used must meet specific biological, chemical and architectural requirements like ECM of the tissue of interest. In acute myocardial infarction, treating the root of the problem by repairing injured tissue is more beneficial to the patient. Inducing more constructive forms of endogenous repair. Thus, patches of acellular scaffolds capable of mimicking the epicardium and ECM should be able to attenuate both cardiac remodelling and adverse cardiac dysfunction

    Sequential post-heading applications for controlling wheat blast: a nine-tear summary of fungicide performance in Brazil.

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    Wheat blast, caused by Pyricularia oryzae Triticum (PoT) lineage, is a major constraint to wheat production, mainly in the tropics of Brazil where severe epidemics have been more frequent. We analyzed disease and wheat yield data from uniform field trials conducted during nine years (2012 to 2020) in order to assess whether the percent control and yield response were influenced by fungicide type, region (tropical or subtropical), and year. Six treatments were selected, all evaluated in at least 19 trials. Two ungicides were applied as solo active ingredients: MANCozeb, and TEBUconazole, and four were premixes: AZOXystrobin + TEBU, TriFLoXystrobin + PROThioconazole, TFLX + TEBU, and PYRAclostrobin + EPOXiconazole. Percent control, calculated from back- ransforming estimates by a meta-analysis network model fitted to the log of the means, ranged from 43 to 58%, with all but PYRA + EPOX showing efficacy greater than 52% on average, not differing among them. The variation in both efficacy and yield response was explained by region and all but TEBU performed better in the subtropics Than in the tropics. Yield response from using three sequential sprays was around two times greater in the subtropics (319 to 532 kg/ha) than in the tropics (149 to 241.3 kg/ha). No significant decline in fungicide efficacy or yield response was observed in nine years of study for any of the fungicides. Our results reinforce the need to improve control by adopting an integrated management approach in the tropics given the poorer performance and lower profitability, especially for the premixes, than in the subtropics. Keywords: Pyricularia oryzae, chemical control, profitability, meta-analysi

    Spotlight on Biomimetic Systems Based on Lyotropic Liquid Crystal

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    The behavior of lyotropic biomimetic systems in drug delivery was reviewed. These behaviors are influenced by drug properties, the initial water content, type of lyotropic liquid crystals (LLC), swell ability, drug loading rate, the presence of ions with higher or less kosmotropic or chaotropic force, and the electrostatic interaction between the drug and the lipid bilayers. The in vivo interaction between LCC—drugs, and the impact on the bioavailability of drugs, was reviewed. The LLC with a different architecture can be formed by the self-assembly of lipids in aqueous medium, and can be tuned by the structures and physical properties of the emulsion. These LLC lamellar phase, cubic phase, and hexagonal phase, possess fascinating viscoelastic properties, which make them useful as a dispersion technology, and a highly ordered, thermodynamically stable internal nanostructure, thereby offering the potential as a sustained drug release matrix for drug delivery. In addition, the biodegradable and biocompatible nature of lipids demonstrates a minimum toxicity and thus, they are used for various routes of administration. This review is not intended to provide a comprehensive overview, but focuses on the advantages over non modified conventional materials and LLC biomimetic properties

    Avaliação e compação de métodos de classificação de imagens de satélites para o mapeamento de estádios de sucessão florestal Assessment and comparison of methods of classification of orbital images for the mapping of forest succession stadiums

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    Este trabalho teve como objetivo comparar as imagens orbitais fornecidas pelos satélites CBERS-2, IRS-P6 e Quickbird para o mapeamento dos estádios de sucessão florestal, utilizando-se diferentes métodos de classificação de imagens digitais. A área de estudo incluiu as reservas de floresta nativa pertencentes ao projeto florestal Macedônia, localizado nos Municípios de Bugre e Ipaba, entre os paralelos 19º19'00"S e 19º24'30"S e os meridianos 42º27'00"W e 42º21'00"W, Estado de Minas Gerais. Foram utilizadas as classificações visual, por pixel e por regiões. Para fins de avaliação da fidedignidade da classificação de cada método, de forma particular, foi gerada a matriz de erros e calculado o índice Kappa. Para testar a significância estatística da diferença entre dois índices Kappa, foi utilizado o teste Z. De maneira geral, os melhores resultados foram as classificações obtidas nos métodos por regiões e visual, apresentando valores de Kappa mais elevados que as classificações por pixel; a imagem resultante da fusão da imagem IRS com a CBERS, classificada pelo método de regiões, obteve o melhor índice Kappa, estando dentro do nível considerado como bom. Os problemas de separação entre as classes resultaram em classificações com baixo nível de exatidão, o que pode ser explicado pela semelhança espectral entre os alvos (estádios inicial, médio e avançado de sucessão florestal), pequena variação entre os valores numéricos dos pixels, existência de sobreposição entre classes e baixa resolução espectral dos sensores.<br>The objective of the present work was to compare the orbital images from the CBERS 2, IRS-P6 and the Quickbird satellites, for the mapping of the stadiums of ecological succession, using different methods of classification of orbital images. The study area included the native forest reserves of the Macedônia forest project, located in the cities of Bugre and Ipaba, between the parallels 19º19'00"S and 19º24'30"S and the meridians 42º27'00"W and 42º21'00"W, Minas Gerais state. The visual, per region and pixel-based classifications were used. In order to evaluate the classification accuracy of each method, a matrix of errors was generated and the Kappa index was calculated. The Z test was used in order to test the statistical significance of the difference between two Kappa indices. Altogether, the best results were the classifications obtained in the visual and region-based methods, with values of kappa higher than those for pixel-based classifications. The image resulting from the fusion of IRS and CBERS images, which were classified through the method of regions, obtained the best Kappa index, and was in the level considered as good. The problems of separation among the classes resulted in classifications with a low degree of accuracy. This can be explained by the spectral similarity present between the targets (initial, medium and advanced stadiums), the small variation among the numerical values of the pixels, the existence of overlapping among classes and the low spectral resolution of sensors
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