Introdução à Globalização

O termo Globalização é normalmente utilizado a propósito de um conjunto de transformações socioeconómicas que vêm atravessando as sociedades contemporâneas em todos os cantos do mundo. Tais transformações constituem um conjunto de novas realidades e problemas que parecem implicar acrescidas dificuldades e novos desafios para os trabalhadores e a acção sindical. Considerando que o conhecimento constitui um instrumento fundamental para a intervenção social, este Manual visa suscitar a reflexão e o debate através de uma iniciação fundamentada às principais questões que a Globalização suscita. Sem respostas milagrosas, nem receitas acabadas, procuraremos contrariar visões derrotistas, ajudando a trilhar e a consolidar caminhos e alternativas. Este Manual procura: Conhecer as principais dinâmicas socioeconómicas do mundo actual; Compreender as questões chave e os conceitos implicados no debate sobre a Globalização; Identificar as principais dimensões da Globalização e conhecer a sua origem e os seus contornos; Colocar e discutir a realidade nacional no contexto da Globalização; Colocar e discutir as questões do trabalho e dos trabalhadores no contexto da Globalização; Identificar as mudanças que a Globalização acarreta para a actividade sindical; Conhecer e discutir dificuldades, reflectindo sobre modos e estratégias para as ultrapassar: Identificar novos desafio

CMB constraints on spatial variations of the vacuum energy density

In a recent article, a simple `spherical bubble' toy model for a spatially varying vacuum energy density was introduced, and type Ia supernovae data was used to constrain it. Here we generalize the model to allow for the fact that we may not necessarily be at the centre of a region with a given set of cosmological parameters, and discuss the constraints on these models coming from Cosmic Microwave Background Radiation data. We find tight constraints on possible spatial variations of the vacuum energy density for any significant deviations from the centre of the bubble and we comment on the relevance of our results.Comment: Minor changes; to appear in Astroparticle Physic

Topology of the universe from COBE-DMR; a wavelet approach

In this paper we pursue a new technique to search for evidence of a finite Universe, making use of a spherical mexican-hat wavelet decomposition of the microwave background fluctuations. Using the information provided by the wavelet coefficients at several scales we test whether compact orientable flat topologies are consistent with the COBE-DMR data. We consider topological sizes ranging from half to twice the horizon size. A scale-scale correlation test indicates that non-trivial topologies with appropriate topological sizes are as consistent with the COBE-DMR data as an infinite universe. Among the finite models the data seems to prefer a Universe which is about the size of the horizon for all but the hypertorus and the triple-twist torus. For the latter the wavelet technique does not seem a good discriminator of scales for the range of topological sizes considered here, while a hypertorus has a preferred size which is 80% of the horizon. This analysis allows us to find a best fit topological size for each model, although cosmic variance might limit our ability to distinguish some of the topologies.Comment: 10 pages, 13 figures (12 coloured), submitted to MNRAS. Figures 1,2 and 3 are not included but a complete version of the paper with high resolution figures can be downloaded from (http://www.mrao.cam.ac.uk/~graca/topol/

Os caminhos que conduzem uma valise: entre os espaços e os alimentos em A valise do professor

A literatura feminina em uma faculdade de Letras como a UFRJ, onde a maioria dos alunos são mulheres, não parece fazer parte integral do currículo base da graduação e nem da pesquisa sendo realizada na Universidade. Uma literatura feminina não produzida no Brasil parece estar ainda mais a margem nas pesquisas. No entanto, ela existe e sua produção chama atenção tanto qualitativa como quantitativamente, ainda que persista em torno dela uma questão: qual é o seu lugar no sistema da literatura e, de forma mais ampla, no sistema da cultura. O presente trabalho tem como objeto de estudo o livro A valise do professor, da autora japonesa Kawakami Hiromi, e propõe a revisão bibliográfica e a análise textual e discursiva da obra. No tocante aos objetivos específicos, há que se atentar para os modos de representação dos espaços e da alimentação feitos na obra, bem como a caracterização das personagens a partir de modos de vinculação com valor emocional e social. Dentro do enredo, os espaços, que poderiam ser localizados em qualquer lugar do mundo se já não soubéssemos que se trata de uma literatura japonesa, conduzem o relacionamento das personagens principais, enquanto as comidas, por mais diferentes que sejam, são descritas de forma a aproximá-las dos leitores, mostram como eles se relacionam dando profundidade e ligamento à trama

Topology of non-linear structure in the 2dF Galaxy Redshift Survey

We study the evolution of non-linear structure as a function of scale in samples from the 2dF Galaxy Redshift Survey, constituting over 221 000 galaxies at a median redshift of z=0.11. The two flux-limited galaxy samples, located near the southern galactic pole and the galactic equator, are smoothed with Gaussian filters of width ranging from 5 to 8 Mpc/h to produce a continuous galaxy density field. The topological genus statistic is used to measure the relative abundance of overdense clusters to void regions at each scale; these results are compared to the predictions of analytic theory, in the form of the genus statistic for i) the linear regime case of a Gaussian random field; and ii) a first-order perturbative expansion of the weakly non-linear evolved field. The measurements demonstrate a statistically significant detection of an asymmetry in the genus statistic between regions corresponding to low- and high-density volumes of the universe. We attribute the asymmetry to the non-linear effects of gravitational evolution and biased galaxy formation, and demonstrate that these effects evolve as a function of scale. We find that neither analytic prescription satisfactorily reproduces the measurements, though the weakly non-linear theory yields substantially better results in some cases, and we discuss the potential explanations for this result.Comment: 13 pages, matching proof to be published in MNRAS; new version adds reference and corrects figure

Os processos de reprodutibilidade nas obras de arte para além do esgotamento artístico: revisitação, citação e inovação

Não querendo tratar-se, exclusivamente de mais uma dissertação sobre a figura mitológica de Orfeu, esta pesquiza procura, através desse signo, evidenciar um padrão de repetição no meio artístico, em especial no âmbito das artes visuais e da poesia. A repetição é um processo que possibilita a aprendizagem e a correção de erros passados, tendo potencial para se constituir motor de uma evolução, transformando-se assim num ato de criação. Orfeu tornou-se uma charneira a partir da época medieval, charneira que cada corrente artística utiliza para repensar as origens da arte e, particularmente, o estatuto do artista oprimido. Este processo leva-nos à revista Orpheu, refletindo sobre poetas e artistas lusobrasileiros que usam Orfeu como figura representativa das suas problemáticas e preocupações sociais. Uma ponderação sobre as diferentes representações da figura na pintura, no teatro e na poesia, atravessando vários séculos, permite tirar conclusões sobre a sua importância neste contexto, que não ficam, naturalmente, concluídas com esta pesquisa.Not wanting to be, exclusively, another dissertation on the mythological figure of Orpheus, this research seeks, through this sign, to evidence a pattern of repetition in the artistic world, especially in the scope of visual arts and poetry. Repetition is a process that makes it possible to learn and correct past mistakes, having the potential to be an evolutionary engine, transforming itself into an act of creation. Orpheus became a hinge from the medieval period, a hinge that every artistic current use to rethink the origins of art and, particularly, the status of the oppressed artist. This process leads us to Orpheu magazine, reflecting on Portuguese-Brazilian poets and artists who use Orpheus as a representative figure of their social problems and concerns. A consideration of the different representations of the figure in painting, theater and poetry, crossing several centuries, allows us to draw conclusions about its importance in this context, which are not, of course, concluded with this research

Constraints on the Detectability of Cosmic Topology from Observational Uncertainties

Recent observational results suggest that our universe is nearly flat and well modelled within a $\Lambda$CDM framework. The observed values of $\Omega_{m}$ and $\Omega_{\Lambda}$ inevitably involve uncertainties. Motivated by this, we make a systematic study of the necessary and sufficient conditions for undetectability as well as detectability (in principle) of cosmic topology (using pattern repetition) in presence of such uncertainties. We do this by developing two complementary methods to determine detectability for nearly flat universes. Using the first method we derive analytical conditions for undetectability for infinite redshift, the accuracy of which is then confirmed by the second method. Estimates based on WMAP data together with other measurements of the density parameters are used to illustrate both methods, which are shown to provide very similar results for high redshifts.Comment: 16 pages, 1 figure, LaTeX2

New 2,4,5-triarylimidazoles based on a phenylalanine core: synthesis, photophysical characterization and evaluation as fluorimetric chemosensors for ion recognition

Novel fluorescent 4,5-diarylimidazolyl-phenylalanines 3a-d were prepared by reaction of N-tert-butyloxycarbonyl-4-formylphenylalanine methyl ester and appropriate (hetero)aromatic diones. The photophysical properties of these new unnatural amino acids were evaluated by UV-Vis absorption and fluorescence spectroscopy in solvents of different character and aqueous mixtures with acetonitrile. They were evaluated as novel amino acid based fluorimetric chemosensors for ions through spectrophotometric and spectrofluorimetric titrations with biologically and analytically important anions and cations such as F-, OH-, Cu2+ and Fe3+. The results indicate that there was a strong interaction through the donor N, O and S atoms at the side chain, especially for 4,5-di(furan-2’-yl)imidazolyl-phenylalanine 3a and 4,5-di(thiophen-2’-yl)imidazolyl-phenylalanine 3b with Cu2+ and Fe3+, in a 1:1 complex stoichiometry. The photophysical and metal ion sensing properties of these amino acids suggest that they can be suitable for incorporation into chemosensory peptidic frameworks.Thanks are due to Fundação para a Ciência e Tecnologia (FCT-Portugal) and FEDER-COMPETE for financial support through Centro de Química [PEst-C/QUI/UI0686/2011 (F-COMP-01-0124-FEDER-022716)] and a PhD grant to C.I.C. Esteves (SFRH/BD/68360/2010). The NMR spectrometer Bruker Avance III 400 is part of the National NMR Network and was purchased with funds from FCT and FEDER.info:eu-repo/semantics/publishedVersio

Constraints on Inflation

A short introduction to structure formation is given, followed by a discussion of the possible characteristics of the initial perturbations assuming a generic inflationary origin. Observational data related to large-scale structure and the cosmic microwave background radiation is then used in an attempt to constrain the characteristics of such perturbations. Future directions are also explored. The possibility of direct detection of a stochastic gravitational wave background produced during an inflationary phase in the early Universe is briefly discussed, as well as the available evidence regarding the present value of the total energy density in the Universe.Comment: 24 pages, Latex, no figures, based on talks given at the Cargese School "Cosmology 2000", to be published in New Astronomy, companion paper to astro-ph/000949

Non-Gaussianity in Large Scale Structure and Minkowski Functionals

Minkowski Functionals (MFs) are topological statistics that have become one of many standard tools used for investigating the statistical properties of cosmological random fields. They have found regular use in studies of departures from Gaussianity in a number of important cosmological scenarios. Important examples include the Cosmic Microwave Background (CMB), weak lensing studies, 21cm surveys and large scale structure (LSS). To lowest order the MFs depend on three generalised skewness parameters that can be shown to probe the bispectrum with differing weights. Recent studies have advocated the use of a power spectrum associated with the bispectrum, called the skew-spectrum, that has more power to distinguish between various contributions to the bispectrum than the conventional formalism adopted when using the Minkowski Functionals. In this article we review the motivations for studying non-Gaussianity and emphasize the importance of the momentum dependence of higher order correlators in investigating both inflationary and early Universe models as well as analytical models for gravitational instability. We then introduce the skew-spectra, applied to galaxy surveys, as a tool for investigating various models for primordial and gravitationally induced non-Gaussianities. We present analytical expressions for the skew-spectra for the density field and divergence of the velocity field in 3D and for projected surveys as a function of redshift and a smoothing angular scale. A Gaussian window function is assumed throughout this paper. Analytical results are derived for the case of gravitationally induced non-Gaussianity. These results can be generalised to incorporate redshift space effects. This will be useful in probing primordial and gravitationally induced non-Gaussianity from ongoing and future galaxy surveys.Comment: 24 Pages, 12 figure