Sensores baseados em nanotubos de carbono funcionalizados por ligação não-covalente

A pesquisa na área dos nanomateriais de carbono, como os nanotubos de carbono (CNTs), tem crescido muito rapidamente devido às suas propriedades térmicas, eletrónicas e mecânicas. Muitos esforços têm sido realizados para aumentar a solubilidade destes materiais em diversos solventes e obter dispersões estáveis. Uma das estratégias para dispersar os CNTs consiste na funcionalização química, que apresenta como desvantagem a destruição da estrutura sp2 do carbono destes materiais. Neste últimos anos surgiram vários estudos baseados na funcionalização não-covalente com o intuito de manter as suas propriedades estruturais. Com este fim, tem sido utilizadas estruturas poliaromáticas substituídas como perilenos e pirenos que podem estabelecer interações do tipo π-π com a superfície aromática dos CNTs ou do grafeno. Neste trabalho pretende-se apresentar uma revisão bibliográfica da utilização da funcionalização nãocovalente no desenvolvimento de sensores e biossensores eletroquímicos em substrato de materiais nanoestruturados de carbono (MWCNTs, SWCNTs, grafeno)

Análise de intervisibilidade um caso de estudo em Valença, Portugal

As questões ligadas ao estudo da visibilidade de cenários naturais ou artificiais são consideradas de grande importância na elaboração e implantação de projectos, pois permitem a avaliação das alterações nos aspectos visuais do território através de simulações de cenários e da visualização tridimensional. O presente trabalho apresenta um arcabouço teórico básico referente à análise de intervisibilidade, através de revisão bibliográfica, e mostra um caso da aplicação prática dessa análise para o estudo da visibilidade de alguns elementos da paisagem do Concelho de Valença, Portugal. Os resultados são apresentados através de mapas de visibilidade para diferentes raios de alcance e alturas de visibilidade e mostram uma avaliação geral da visibilidade em Valença

Conjugations on the Hardy space H2H^{2}

A conjugation $C$ on a separable complex Hilbert space $\mathcal H$ is an antilinear operator that is isometric and involutive. In this notes, we characterize all conjugations on the Hardy-Hilbert space $H^{2}$ over the disk. In addition, we characterize complex symmetric Toeplitz operators with a special type of these conjugations.Comment:

Correlation of Admission Metrics with Eventual Success in Mathematics Academic Performance of Freshmen in AMAIUB’s Business Curricula

This is a correlational study research design, which aimed to determine the correlation of admission metrics with eventual success in mathematics academic performance of the admitted 177 first year students of Bachelor of Science in Business Informatics and 59 first year students of Bachelor of Science in International Studies. Using Pearson’s product-moment correlation, results showed that there is a significant moderate positive linear relationship between the programmatic admission test scores and Mathematics academic performance of the students in both programmes. The results of the study established the validity of the method for the existing AMAIUB programmatic admission test conceptualized, prepared and implemented by the University. Thus, Programmatic admission metrics tend to predict the eventual success in Mathematics academic performance of freshmen in AMAIUB’s Business Curricula. Keywords: admission test scores, mathematics academic performance, business curricula

Saliency-driven system models for cell analysis with deep learning.

Background and objectivesSaliency refers to the visual perception quality that makes objects in a scene to stand out from others and attract attention. While computational saliency models can simulate the expert's visual attention, there is little evidence about how these models perform when used to predict the cytopathologist's eye fixations. Saliency models may be the key to instrumenting fast object detection on large Pap smear slides under real noisy conditions, artifacts, and cell occlusions. This paper describes how our computational schemes retrieve regions of interest (ROI) of clinical relevance using visual attention models. We also compare the performance of different computed saliency models as part of cell screening tasks, aiming to design a computer-aided diagnosis systems that supports cytopathologists.MethodWe record eye fixation maps from cytopathologists at work, and compare with 13 different saliency prediction algorithms, including deep learning. We develop cell-specific convolutional neural networks (CNN) to investigate the impact of bottom-up and top-down factors on saliency prediction from real routine exams. By combining the eye tracking data from pathologists with computed saliency models, we assess algorithms reliability in identifying clinically relevant cells.ResultsThe proposed cell-specific CNN model outperforms all other saliency prediction methods, particularly regarding the number of false positives. Our algorithm also detects the most clinically relevant cells, which are among the three top salient regions, with accuracy above 98% for all diseases, except carcinoma (87%). Bottom-up methods performed satisfactorily, with saliency maps that enabled ROI detection above 75% for carcinoma and 86% for other pathologies.ConclusionsROIs extraction using our saliency prediction methods enabled ranking the most relevant clinical areas within the image, a viable data reduction strategy to guide automatic analyses of Pap smear slides. Top-down factors for saliency prediction on cell images increases the accuracy of the estimated maps while bottom-up algorithms proved to be useful for predicting the cytopathologist's eye fixations depending on parameters, such as the number of false positive and negative. Our contributions are: comparison among 13 state-of-the-art saliency models to cytopathologists' visual attention and deliver a method that the associate the most conspicuous regions to clinically relevant cells

Widening the perspectives for legume consumption: the case of bioactive non-nutrients

Legume grains have provided essential nutrients in human diets for centuries, being excellent sources of proteins, carbohydrates, fatty acids, and fibers. They also contain several non-nutrients that historically have been connotated as toxic but that in recent years have been shown to have interesting bioactive properties. The discussion on the role of bioactive non-nutrients is becoming more important due to increasing science-based evidence on their potential antioxidant, hypoglycemic, hypolipidemic, and anticarcinogenic properties. At a time when legume-based products consumption is being strongly promoted by national governments and health authorities, there is a need to clearly define the recommended levels of such non-nutrients in human diets. However, there is insufficient data determining the ideal amount of non-nutrients in legume grains, which will exert the most positive health benefits. This is aligned with insufficient studies that clearly demonstrate if the positive health effects are due to the presence of specific non-nutrients or a result of a dietary balance. In fact, rather than looking directly at the individual food components, most nutritional epidemiology studies relate disease risk with the food and dietary patterns. The purpose of this perspective paper is to explore different types of non-nutrients present in legume grains, discuss the current evidence on their health benefits, and provide awareness for the need for more studies to define a recommended amount of each compound to identify the best approaches, either to enhance or reduce their levels.info:eu-repo/semantics/publishedVersio

Efeito dos antioxidantes met?licos e da resina fen?lica nas propriedades de refrat?rios de Al2O3 - SiC - C.

As pr?ticas metal?rgicas associadas ao transporte e pr?-tratamento do gusa submetem os refrat?rios para carros torpedo a uma conjuga??ode solicita??es de natureza qu?mica e f?sica favorecendo os processos de corros?o, eros?o e fratura destes materiais. Os refrat?rios de alto desempenho, sistema Al2O3 - SiC - C, passaram a ser utilizadosno revestimento refrat?rio para carros torpedo a partir dos anos 80 como resposta ?s novas solicita??es introduzidas pelo processo metal?rgico. A forma??o de trincas paralelas ? face quente dos tijolos de Al2O3- SiC - C com posterior lascamento da por??o afetada tem se destacado por ser motivo de encerramento prematuro da campanha do revestimento refrat?rio do carro torpedo. As modifica??es microestruturais destes materiais, combinadas com esfor?os de natureza mec?nica e t?rmica, t?m sido a causa da fratura destes refrat?rios. Portanto, a caracteriza??o destes materiais, por meio de ensaios laboratoriais, permite, atrav?s de uma m?ltipla abordagem do ponto de vista qu?mico e f?sico, um melhor entendimento do seu comportamento. Os resultados obtidos em laborat?rio apontaram que os materiais isentos dos antioxidantes met?licos Si e Al denominados A-0 e B-0 destacaram-se. Os materiais cujos teores de sil?cio foram duplicados e quadruplicados apresentaram melhora nas propriedades mec?nicas ? quente, mas pioraram seu desempenho quanto ? resist?ncia ao dano por choque t?rmico e ao desgaste pela esc?ria. Por outro lado destaca-se, tamb?m, a baixa influ?ncia do tipo de resina nas propriedades dos tijolos apesar daqueles fabricados com a resina comercial Novolacaapresentarem menor resist?ncia mec?nica se comparados com os fabricados com a resina comercial Resol. Em s?ntese, assumindo-se um compromisso entre as propriedades qu?micas (resist?ncia ? oxida??o e ? corros?o pela esc?ria) e f?sicas (resist?ncia mec?nica ? quente e ao dano por choque t?rmico), os resultados dos testes laboratoriais indicaram que o antioxidante met?lico Si pode ser otimizado na formula??o destes materiais com ganhos de propriedades e com potencial de ganho de desempenho destes refrat?rios em servi?o.The metallurgical practices associated to the pig iron transportation and pretreatment submit the torpedo car refractories to a conjugation of demands of chemical and physical nature favoring the corrosion, erosion and fracture processes of these materials. The high performance Al2O3- SiC - C refractories started to be used in torpedo cars at the 1980?s as na answer to the new demands introduced by the metallurgical process. The formation of cracks parallel to the hot face of the Al2O3- SiC - C bricks with subsequent spalling of the affected portion has been shown to be the main reason of premature campaign finishing of the torpedo car lining. The microstructure changes on these materials, combined with mechanical and thermal stresses have been the cause of fracture on these refractories. Therefore, the characterization of these materials by means of laboratory tests allows a better understanding of their behavior through a multiple approach from the chemical and physical point of view. The laboratory tests results obtained indicated better performance of the materials without Si and Al antioxidant agents, designated A-0 and B-0. The materials whose silicon amount was doubled and quadruplicated present improved hot mechanical properties, but their performance in terms of thermal shock and slag wear resistance was worse. On the other hand the low influence of the type of resin in the properties of the bricks also stands out, even though the bricks manufactured with the Novolacacommercial resin presented lower mechanical resistance compared to the bricks manufactured with the Resol commercial resin. In summary, assuming a compromise between the chemical (resistance to the oxidation and corrosion by slag) and the physical (mechanical resistance and resistance to thermal shock damage) properties, the results obtained indicate that the metallic antioxidant Si can be optimized in the formulation of these material with an improvementin properties and a potential of improving the performance of this lining in service

Tumores abdominais raros com crescimento intracardíaco. A propósito de dois casos operados com sucesso

Abdominal tumors that can grow through vascular lumen and spread to the right heart are rare. Although these tumors have different histologic aspects, they may cause similar abdominal and cardiac symptoms and are a serious risk factor for pulmonary embolism and sudden death when they reach the right atrium and tricuspid valve. The best treatment is radical surgical resection of the entire tumor using cardiopulmonary bypass with or without deep hypothermia and total circulatory arrest. We report the cases of two patients, the first with leiomyosarcoma of the inferior vena cava and the other with intravenous leiomyomatosis of the uterus that showed intravascular growth up to right atrium and ventricle, who underwent successful radical resection in a one-stage procedure with the use of cardiopulmonary bypass. We discuss the clinical and histologic aspects and imaging diagnosis and review the literature.Tumores abdominais que crescem pela luz dos vasos e atingem o coração são raros. Estes tumores possuem características histológicas distintas porém causam sintomas abdominais e cardíacos semelhantes e apresentam elevado risco de embolia pulmonar e morte súbita quando atingem o átrio direito e a valva tricúspide. O tratamento mais eficaz é a ressecção cirúrgica radical de todo o tumor usando-se circulação extracorpórea com ou sem hipotermia profunda e parada circulatória total. Relatamos os casos de dois pacientes, o primeiro portador de leiomiossarcoma primário da veia cava inferior e o segundo com leiomiomatose intravascular uterina com crescimento pela veia cava inferior alcançando o átrio e ventrículo direitos, que foram operados com sucesso para ressecção concomitante do tumor primário e de sua extensão intra-cardíaca, com auxílio da circulação extracorpórea. Os aspectos clínicos, laboratoriais e histopatológicos são discutidos e é feita revisão da literatura

Lentil-based snack: development and nutritious properties

Legume grains provide not only a unique nutrient profile essential for good human health, such as protein, fiber, carbohydrates, fatty acids, minerals, vitamins, and phenolic compounds, but they also provide excellent environmental benefits. Besides, they adapt to contemporary food patterns, like flexitarian, vegetarian, vegan, and gluten-free. However, legume consumption continues to be less than desired, opening new opportunities for different intake alternatives. Furthermore, due to agriculture growth and unbalanced animal consumption the food industry aims to increase and diversify alternative protein formulations. Amongst the legumes, lentils have a fast-cooking time, high arginine, antioxidant flavonoids, and a low glycemic index which helps avoid peaks in blood glucose, improving metabolic control, and recent epidemiological studies suggest that they may help combat cardiovascular disease and diabetes mellitus, both with high prevalence worldwide. Based on this knowledge, we developed a muffin in which commercial oatmeal was partially substituted with lentil flour. The nutritional value of the snack was evaluated, and it was also performed microbiological analyses. The lentil-based muffin had higher protein and fiber and lower carbohydrate content compared to the oatmeal-based muffin. The aim of these muffins is that they are suitable for all consumers, including diabetics. This project seeks to be a central element in the promotion of one of the oldest grain legumes, contributing to an increase in its consumption and consequent commercial valorization.info:eu-repo/semantics/publishedVersio