A leitura e a educação intercultural : exigência de novas práticas educativas

Este artigo pretende discutir questões fundamentais acerca da formação de leitores, focalizando a problemática acerca do ensino da leitura e da iliteracia e suas consequências socioculturais, mas sobretudo o impacto que a leitura esta pode provocar enquanto sistema simbólico na construção de visão de mundo e apropriação da realidade. No mundo contemporâneo é impossível se pensar em leitura e educação sem reflectir profundamente acerca da interculturalidade e da trama que aí se tece para se (re)construir a história humana, principalmente no sentido de se corrigir as situações que implicam em desigualdade, preconceito e racismo. Nessa perspectiva iremos assumir e sublinhar o discurso de autores significativos para estas duas áreas temáticas, dando ênfase aos autores Freire e Bakhtine, articulando-os com outros investigadores, também, relevantes para o estudo da Leitura e da Educação Intercultural

High resolution mass spectrometry for quantitative analysis and untargeted screening of algal toxins in mussels and passive samplers

Measurement of marine algal toxins has traditionally focussed on shellfish monitoring while, over the last decade, passive sampling has been introduced as a complementary tool for exploratory studies. Since 2011, liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been adopted as the EU reference method (No.15/2011) for detection and quantitation of lipophilic toxins. Traditional LC-MS approaches have been based on low-resolution mass spectrometry (LRMS), however, advances in instrument platforms have led to a heightened interest in the use of high-resolution mass spectrometry (HRMS) for toxin detection. This work describes the use of HRMS in combination with passive sampling as a progressive approach to marine algal toxin surveys. Experiments focused on comparison of LRMS and HRMS for determination of a broad range of toxins in shellfish and passive samplers. Matrix effects are an important issue to address in LC-MS; therefore, this phenomenon was evaluated for mussels (Mytilus galloprovincialis) and passive samplers using LRMS (triple quadrupole) and HRMS (quadrupole time-of-flight and Orbitrap) instruments. Matrix-matched calibration solutions containing okadaic acid and dinophysistoxins, pectenotoxin, azaspiracids, yessotoxins, domoic acid, pinnatoxins, gymnodimine A and 13-desmethyl spirolide C were prepared. Similar matrix effects were observed on all instruments types. Most notably, there was ion enhancement for pectenotoxins, okadaic acid/dinophysistoxins on one hand, and ion suppression for yessotoxins on the other. Interestingly, the ion selected for quantitation of PTX2 also influenced the magnitude of matrix effects, with the sodium adduct typically exhibiting less susceptibility to matrix effects than the ammonium adduct. As expected, mussel as a biological matrix, quantitatively produced significantly more matrix effects than passive sampler extracts, irrespective of toxin. Sample dilution was demonstrated as an effective measure to reduce matrix effects for all compounds, and was found to be particularly useful for the non-targeted approach. Limits of detection and method accuracy were comparable between the systems tested, demonstrating the applicability of HRMS as an effective tool for screening and quantitative analysis. HRMS offers the advantage of untargeted analysis, meaning that datasets can be retrospectively analysed. HRMS (full scan) chromatograms of passive samplers yielded significantly less complex data sets than mussels, and were thus more easily screened for unknowns. Consequently, we recommend the use of HRMS in combination with passive sampling for studies investigating emerging or hitherto uncharacterised toxins.

Ler para argumentar: estratégias dinamizadoras de aprendizagem

Trabalho de Projeto apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ciências da Educação: área de especialização em Animação da Leitura realizado sob a orientação científica da Prof.ª Doutora Maria Cristina Vieira da Silva

Scaffolds for controlled release of cartilage growth factors

International audience

A bidomain threshold model of propagating calcium waves

We present a bidomain fire-diffuse-fire model that facilitates mathematical analysis of propagating waves of elevated intracellular calcium (Ca) in living cells. Modelling Ca release as a threshold process allows the explicit construction of travelling wave solutions to probe the dependence of Ca wave speed on physiologically important parameters such as the threshold for Ca release from the endoplasmic reticulum (ER) to the cytosol, the rate of Ca resequestration from the cytosol to the ER, and the total [Ca] (cytosolic plus ER). Interestingly, linear stability analysis of the bidomain fire-diffuse-fire model predicts the onset of dynamic wave instabilities leading to the emergence of Ca waves that propagate in a back-and-forth manner. Numerical simulations are used to confirm the presence of these so-called "tango waves" and the dependence of Ca wave speed on the total [Ca]. The original publication is available at www.springerlink.com (Journal of Mathematical Biology)

The Duchamp Research Portal: Moving an Idea to Proof of Concept

Presentation from the MARAC conference in Pittsburgh, PA on April 14–16, 2016. S15 - The Duchamp Research Portal: Moving an Idea to Proof of Concept.

In the Beginning: Building an Archive from the Ground Up

Presentation from the MARAC conference in Pittsburgh, PA on April 14–16, 2016. S23 - In the Beginning: Building an Archive from the Ground Up

Communities in Collaboration: Building the Empire Archival Discovery Cooperative

Presentation from the MARAC conference in Pittsburgh, PA on April 14–16, 2016. S24; - Pittsburgh Pop-Up #2.

Pittsburgh and Philadelphia Can Work Together: Processing the Arlen Specter Collection at the University of Pittsburgh

Presentation from the MARAC conference in Pittsburgh, PA on April 14–16, 2016. S2 - Making Friends: The Highs, Lows, and Challenges of Inter-Repository Archival Relationships

CHARACTERIZATION OF POLYUBIQUITIN CHAINS BY MASS SPECTROMETRY

The work outlined in this dissertation will allow biochemists and cellular biologists to characterize polyubiquitin chains involved in their cellular environment by following a facile mass spectrometric based workflow. The characterization of polyubiquitin chains has been of interest since their discovery in 1984. The profound effects of ubiquitination on the movement and processing of cellular proteins depend exclusively on the structures of mono and polyubiquitin modifications anchored or unanchored on the protein within the cellular environment. However, structure-function studies have been hindered by the difficulty in identifying complex chain structures due to limited instrument capabilities of the past. Genetic mutations or reiterative immunoprecipitations have been used previously to characterize the polyubiquitin chains, but their tedium makes it difficult to study a broad ubiquitinome. Top-down and middle-out mass spectral based proteomic studies have been reported for polyubiquitin and have had success in characterizing parts of the chain, but no method to date has been successful at differentiating all theoretical ubiquitin chain isomers (ubiquitin chain lengths from dimer to tetramer alone have 1340 possible isomers). The workflow presented here can identify chain length, topology and linkages present using a chromatographic-time-scale compatible, LC-MS/MS based workflow. To accomplish this feat, the strategy had to exploit the most recent advances in top-down mass spectrometry. This included the most advanced electron transfer dissociation (ETD) activation and sensitivity for large masses from the orbitrap Fusion Lumos. The spectral interpretation had to be done manually with the aid of a graphical interface to assign mass shifts because of a lack of software capable to interpret fragmentation across isopeptide linkages. However, the method outlined can be applied to any mass spectral based system granted it results in extensive fragmentation across the polyubiquitin chain; making this method adaptable to future advances in the field.

Identifying wind power ramp causes from multivariate datasets: a methodological proposal and its application to reanalysis data.

Forecasting abrupt variations in wind power generation (the so-called ramps) helps achieve large scale wind power integration. One of the main issues to be confronted when addressing wind power ramp forecasting is the way in which relevant information is identified from large datasets to optimally feed forecasting models. To this end, an innovative methodology oriented to systematically relate multivariate datasets to ramp events is presented. The methodology comprises two stages: the identification of relevant features in the data and the assessment of the dependence between these features and ramp occurrence. As a test case, the proposed methodology was employed to explore the relationships between atmospheric dynamics at the global/synoptic scales and ramp events experienced in two wind farms located in Spain. The achieved results suggested different connection degrees between these atmospheric scales and ramp occurrence. For one of the wind farms, it was found that ramp events could be partly explained from regional circulations and zonal pressure gradients. To perform a comprehensive analysis of ramp underlying causes, the proposed methodology could be applied to datasets related to other stages of the wind-topower conversion chain.

Perplejidades y contradicciones: La economía mundial en el nuevo siglo

Estamos entrando en el siglo XXI con cambios importantísimos en el sistema económico mundial. Después de un largo período de 27 años -iniciado en 1967-, en que la economía mundial se enfrentó a una caída en sus principales índices de crecimiento y se vio sumida en varias crisis financieras, el abandono de los intereses altos y de las políticas de sobrevaloración cambiaria, practicadas en los EE.UU en los años ochenta, conduce a una nueva situación de recuperación económica a escala internacional.En este nuevo marco, resulta normal que el comercio mundial alcanzara un nuevo auge. Sin embargo bajo la influencia del pensamiento neoliberal, se confunde la expansión del comercio con el crecimiento del “libre mercado”. La realidad es completamente diferente: la expansión del comercio mundial se hace bajo la forma de un creciente monopolio de los mercados mundiales por las grandes empresas globales o transnacionales. Con arreglo a esta nueva fase de globalización, ellas se funden en grupos cada vez más planetarios y generan varios mecanismos de actuación conjunta.

Tres ensayos sobre crédito, liquidez y capital bancario

El articulo de Miller, 1977, destacó el papel de la liquidez para la determinación de los precios. Desde entonces, varios estudios han tratado de explicar los determinantes de la liquidez, y de formalizar sus implicaciones para la toma de decisiones de los agentes. La preocupación sobre el papel de la liquidez no es algo tan nuevo como se podría pensar. Dos ejemplos, sobre la importancia de la liquidez para la determinación de los precios y sobre cómo la liquidez y el capital estan relacionados, son la crisis de los bancos florentinos del siglo XIV y el colapso del mercado de los tulipanes en el siglo XVII. El primer sistema bancario que funcionaba bajo criterios modernos, nació en Florencia. Los bancos florentinos eran entidades familiares, altamente internacionales, cuyo negocio se centraba en los préstamos comerciales y la gestión de efectivo. El impago de la corona británica alrededor del año 1340, llevó a la bancarrota de los bancos florentinos más internacionales. Los bancos domésticos, a fin de garantizar la tenencia de efectivo, respondieron redujendo el flujo de crédito a la economía real y vendiendo bonos de la República. La elevada liquidez de dichos activos garantizaba, en principio, una rápida recuperación del dinero invertido. A pesar de ello, el exceso de oferta de bonos en el mercado, provocó una caída abrupta de los precios. Las autoridades, para intentar garantizar la estabilidad del sistema, reaccionaron mediante la compra de bonos en el mercado. A pesar de lo cuál, el sistema bancario colapsó, y la crisis económica se extendió durante 40 años. Familiar, ¿ verdad ?. Otro buen ejemplo, de cómo las restricciones de capital y la liquidez interactúan, fue el estallido de la burbuja del mercado de los tulipanes del año 1636. La ausencia de compradores en una subasta rutinaria de tulipanes, en Harleem, propicio la caida de los precios...

La question des stéréotypes sexuels dans les aspirations professionnelles des filles et des garçons de 4e et 5e secondaire

Cet essai traite de la présence des stéréotypes sexuels en rapport avec les aspirations professionnelles des filles et des garçons de 4e et 5e secondaire. Ainsi, malgré le fait que divers travaux de recherche se sont penchés sur les facteurs d’influence des choix d’orientation d’élèves du secondaire, peu d’études se sont spécifiquement attardées à considérer la place qu’occupent les stéréotypes sexuels dans les aspirations professionnelles de ces jeunes. Pour ce faire, une analyse des aspirations professionnelles recueillies l’aide du Questionnaire de maturité vocationnelle (QMV) (Fangeaux, Gingras, Yergeau, Yergeau et Thériault, 2014; Gingras, Yergeau et Bolduc, 2014) administré à 1416 jeunes a été effectuée de façon globale et en fonction du genre. Cette démarche a permis de procéder au classement des aspirations professionnelles des filles et des garçons selon le secteur de la formation professionnelle et technique représenté ainsi qu’en fonction de la profession mentionnée. Les résultats démontrent que ces élèves ont tendance à indiquer des aspirations professionnelles qui se retrouvent dans certains secteurs du monde du travail en particulier et que la majorité de celles-ci réfèrent à des stéréotypes sexuels. En ce sens, les filles aspirent généralement à des professions et des secteurs du monde du travail qui sont traditionnellement féminins alors que pour les garçons, ces secteurs et professions sont dans la plupart des cas, traditionnellement masculins. D’autres recherches pourraient être menées afin quantifier l’influence des stéréotypes sexuels sur les aspirations professionnelles de ces jeunes ainsi que pour vérifier si ceux-ci se maintiennent ou non dans le temps.

First record of Ocinebrina nicolai (Mollusca: Gastropoda: Muricidae: Ocenebrinae) in North-Eastern Atlantic waters

Ocinebrina nicolai Monterosato, 1884 a marine mollusc belonging to the Muricidae family is reported from Algarve, south coast of Portugal for the first time and is a new record for the biodiversity of the Portuguese malacological fauna and northeastern Atlantic waters. This species with a medium-size shell for the genus (14–16 mm) was initially sampled during a baseline project that studied marine biotopes in the central Algarve region. This short note presents a brief diagnosis of the species, provides local information on geographical distribution, habitat, and compares it with other congeneric species found in Portugal: Ocinebrina aciculata (Lamarck, 1822) and Ocinebrina edwardsii (Payraudeau, 1826).