477 research outputs found

    Matemática Financeira e Planilhas Eletrônicas: Uma Abordagem com a Incorporação de Recursos Computacionais

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    http://dx.doi.org/10.5902/2179460X14623This paper has as its goal to propose a new alternative approach to the progressions and financial math teaching, with the incorporation of technological resources. One of the concepts that used is the study of geometric and arithmetic progressions. In order to study those, an approach based on recurrence relations is proposed. With the goal of stimulating the algebraic manipulation and understanding of the financial math formulas variables, it is proposed the incorporation of the technological resources, in particular, of electronic spreadsheets, in classes about the theme. Through the tool, it is proposed the viability of financial math simulators in the classroom, seeking the diversification of activities.Este trabalho tem por objetivo propor uma abordagem alternativa para o ensino de progressões e matemática financeira, com a incorporação de recursos tecnológicos. Um dos conceitos utilizados é o estudo de progressões aritméticas e geométricas. Para o estudo destes, propomos a abordagem por meio da resolução de relações de recorrência. Com o objetivo de estimular a manipulação algébrica e a compreensão das variáveis das fórmulas de matemática financeira, propomos a incorporação de recursos tecnológicos, em particular, das planilhas eletrônicas, nas aulas sobre o tema. Por meio dessa ferramenta, propomos a viabilização da construção de simuladores de matemática financeira em sala de aula, visando a diversificação das atividades

    A prática construcionista e o pensamento computacional como estratégias para manifestações do pensamento algébrico

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    Nesse artigo é abordada a viabilidade da combinação de estratégias referentes ao construcionismo e pensamento computacional para promoção da educação algébrica. Com base em referencial teórico sobre essas vertentes teóricas, discute-se sobre como ambientes de aprendizagem que contemplem a resolução de problemas matemáticos na perspectiva construcionista podem favorecer a explicitação de aspectos necessários para o desenvolvimento do pensamento algébrico. Por fim, aborda-se como o uso de uma plataforma de programação visual pode auxiliar nesse processo. O cenário exposto permite perspectivar que atividades educativas que contemplam o desenvolvimento de aplicativos de execução de cálculos com a ferramenta App Inventor estimulam a manifestação do pensamento algébrico, justificado pelo fato de contemplar abstração, uso de linguagem simbólica e protagonismo discente de forma combinada

    Cayley: Aplicativo para o aprendizado de matrizes, determinantes e sistemas lineares

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    This paper presents the proposal for the development of the Cayley app,idealized as a complementary result of an extension project at a federal teachinginstitution in the city of Irati. The application is intended to help the student in thelearning of the matrices, determinants and linear systems, and it is being developed through the use of the App Inventor platform. In addition to contemplating a section with calculators referring to the theme, the application will have a section containing theoretical aspects regarding the theme

    A multi-targeted approach to suppress tumor-promoting inflammation

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    Cancers harbor significant genetic heterogeneity and patterns of relapse following many therapies are due to evolved resistance to treatment. While efforts have been made to combine targeted therapies, significant levels of toxicity have stymied efforts to effectively treat cancer with multi-drug combinations using currently approved therapeutics. We discuss the relationship between tumor-promoting inflammation and cancer as part of a larger effort to develop a broad-spectrum therapeutic approach aimed at a wide range of targets to address this heterogeneity. Specifically, macrophage migration inhibitory factor, cyclooxygenase-2, transcription factor nuclear factor-κB, tumor necrosis factor alpha, inducible nitric oxide synthase, protein kinase B, and CXC chemokines are reviewed as important antiinflammatory targets while curcumin, resveratrol, epigallocatechin gallate, genistein, lycopene, and anthocyanins are reviewed as low-cost, low toxicity means by which these targets might all be reached simultaneously. Future translational work will need to assess the resulting synergies of rationally designed antiinflammatory mixtures (employing low-toxicity constituents), and then combine this with similar approaches targeting the most important pathways across the range of cancer hallmark phenotypes

    X-ray emission from the Sombrero galaxy: discrete sources

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    We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

    Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

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    A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets

    Performance of the CMS Cathode Strip Chambers with Cosmic Rays

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    The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

    Specificity and disease in the ubiquitin system

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    Post-translational modification (PTM) of proteins by ubiquitination is an essential cellular regulatory process. Such regulation drives the cell cycle and cell division, signalling and secretory pathways, DNA replication and repair processes and protein quality control and degradation pathways. A huge range of ubiquitin signals can be generated depending on the specificity and catalytic activity of the enzymes required for attachment of ubiquitin to a given target. As a consequence of its importance to eukaryotic life, dysfunction in the ubiquitin system leads to many disease states, including cancers and neurodegeneration. This review takes a retrospective look at our progress in understanding the molecular mechanisms that govern the specificity of ubiquitin conjugation

    Performance and Operation of the CMS Electromagnetic Calorimeter

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    The operation and general performance of the CMS electromagnetic calorimeter using cosmic-ray muons are described. These muons were recorded after the closure of the CMS detector in late 2008. The calorimeter is made of lead tungstate crystals and the overall status of the 75848 channels corresponding to the barrel and endcap detectors is reported. The stability of crucial operational parameters, such as high voltage, temperature and electronic noise, is summarised and the performance of the light monitoring system is presented

    Mechanism and disease-association of E2 conjugating enzymes:lessons from UBE2T and UBE2L3

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    Ubiquitin signalling is a fundamental eukaryotic regulatory system, controlling diverse cellular functions. A cascade of E1, E2, and E3 enzymes is required for assembly of distinct signals, whereas an array of deubiquitinases and ubiquitin-binding modules edit, remove, and translate the signals. In the centre of this cascade sits the E2-conjugating enzyme, relaying activated ubiquitin from the E1 activating enzyme to the substrate, usually via an E3 ubiquitin ligase. Many disease states are associated with dysfunction of ubiquitin signalling, with the E3s being a particular focus. However, recent evidence demonstrates that mutations or impairment of the E2s can lead to severe disease states, including chromosome instability syndromes, cancer predisposition, and immunological disorders. Given their relevance to diseases, E2s may represent an important class of therapeutic targets. In the present study, we review the current understanding of the mechanism of this important family of enzymes, and the role of selected E2s in disease
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