Avaliação operacional do controle mecânico de plantas aquáticas imersas no reservatório de Jupiá

O presente trabalho foi realizado com o objetivo de estudar a coleta e o descarte de plantas aquáticas em diferentes locais e infestações do sistema Tietê/Paraná, no reservatório de Jupiá. A operação foi realizada com auxílio de instrumentação instalada em uma colhedora de plantas aquáticas, com sistema de GPS dotado de sinal de correção diferencial. Os tempos gastos para carregar e descarregar a colhedora foram determinados por cronometragem, e a distância do ponto final de coleta ao ponto de descarte e o tempo de deslocamento, por cronometragem e uso de GPS convencional. em algumas coletas foram demarcados polígonos, instruindo-se o operador a trabalhar exclusivamente na área correspondente. A interpretação dos resultados permitiu determinar a participação do tempo de coleta em relação ao tempo total de operação, indicando um valor significativo do ponto de vista operacional (>70%). Considerando o descarte em áreas infestadas com taboa, o deslocamento total médio foi de apenas 383 m, com gasto médio de 200,96 s. Os valores de capacidade operacional da colhedora oscilaram entre 0,23 e 1,60 ha h-1, indicando valor médio de 4,48 ha dia-1. A maior limitação à capacidade operacional associou-se à velocidade média de deslocamento, com maior agravante em áreas com altas infestações ou profundas. Considerando-se o deslocamento da colhedora, houve grande dificuldade de orientação em condições normais de operação, inviabilizando a manutenção de espaçamentos uniformes entre as faixas de coleta e sobrepondo as passagens. Conclui-se que a avaliação operacional indicou a impossibilidade de operar a colhedora sem o auxílio de um sistema de navegação que permita orientar a sua movimentação nas áreas de controle.

O latim, uma língua morta?: uma metáfora em análise: o olhar da lingüística aplicada e suas implicações para o ensino

The focus of this research is the teaching of the Latin language. Due to the fact that its teaching has been facing a growing crisis in the last four decades, which currently persists, we ponder about external and internal causes of its decline, aiming at pointing out an alternative that enable us to find a way out of this situation. So, our research questions mainly concern how the teaching of Latin is viewed amongst the academic society, also investigating if it has kept up with the development of the scientific reflection about human language and the new approaches on language teaching. Furthermore, we analyse the contribution that the study of Latin can provide to the academic formation of language teachers and try to identify the areas of knowledge that can contribute to a reshaping of its teaching. Based on these guidelines, we have established as the goals of this research: 1) to reflect about the current situation of the teaching of Latin and the causes of its decline; 2) to determine its social representation among teachers and students of the Language Courses, as a way of defining the role it fulfills in the academic formation of teachers; 3) to accomplish an exploratory study of some handbooks that show alternative proposals on how to teach Latin, in order to detect their adequacy to current times and to the goals of the academic study of languages; 4) to offer an alternative proposal on how to teach Latin that takes into account the principles of Applied Linguistics, considering the socio-historical and cultural aspects of the language, enabling it to meet the requirements set by modern times. This research is divided into two parts. The first part presents the theoretical framework. We map the studies about Latin teaching inside and outside Brazil and argue against the concept of Latin being a dead language, presenting arguments set on changing this view. Then we describe and comment the notions of literacy, genre and culture, which helped us understand the reasons for the decline of the teaching of Latin and to point out suitable ways to overcome the crisis. The second part is dedicated to reflecting on the literacy practices in Latin teaching. We began by examining the answers to the questionnaires given to students and teachers about the view of Latin in the Language Courses; then we reflect on the teaching-learning of Latin as an academic literacy practice followed by an analysis of the didactic material used in teaching Latin. Finally, we suggest an approach of the familiar letter genre in ancient Rome as a means of teaching Latin in a contextualized way

Trilepton signal for supersymmetry at the Fermilab Tevatron reexamined

Within a wide class of models, the CERN LEP2 lower limit of 95 GeV on the chargino mass implies gluinos are heavier than similar to 300 GeV. In this case electroweak (W) over tilde(1)(W) over tilde(1) production and (W) over tilde(1)(Z) over tilde(2) production are the dominant supersymmerry (SUSY) processes at the Fermilab Tevatron, and the extensively examined isolated trilepton signal From (W) over tilde(1)(Z) over tilde(2) production assumes an even greater importance. We update our previous calculations of the SUSY reach of luminosity upgrades of the Fermilab Tevatron in this channel incorporating (i) decay matrix elements in the computation of the momenta of leptons from chargino and neutralino decays, (ii) the trilepton background from W*Z* and W*gamma* production which, though neglected in previous analyses, turns out to be the dominant background, and finally, (iii) modified sets of cuts designed to reduce these new backgrounds and increase the range of model parameters for which the signal is observable. We show our improved projections for the reach for SUSY of both the Fermilab Main Injector and the proposed TeV33 upgrade. We also present opposite sign same flavor dilepton invariant mass distributions as well as the p(T) distributions of leptons in SUSY trilepton events, and comment upon how the inclusion of decay matrix elements impacts upon the Tevatron reach, as well as upon the extraction of neutralino masses.

A new proposal for the picture changing operators in the minimal pure spinor formalism

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Light composite Higgs boson from the normalized Bethe-Salpeter equation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Chaotic thermalization in Yang-Mills-Higgs theory on a spacial lattice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Generalized point interactions in one-dimensional quantum mechanics

There is a four-parameter family of point interactions in one-dimensional quantum mechanics. They represent all possible self-adjoint extensions of the kinetic energy operator. If time-reversal invariance is imposed, the number of parameters is reduced to three. One of these point interactions is the familiar delta function potential but the other generalized ones do not seem to be widely known. We present a pedestrian approach to this subject and comment on a recent controversy in the literature concerning the so-called delta' interaction. We emphasize that there is little resemblance between the delta' interaction and what its name suggests.

RESONANCE PRODUCTION IN PERIPHERAL HEAVY-ION COLLISIONS

Heavy-ion collisions at ultrarelativistic energies may be used as a powerful source of photons and pomerons. We compute the rates for pseudoscalar meson production through two-photon and two-pomeron scattering, at energies that will be available at RHIC and LHC. Light mesons will mostly be produced by pomeron fusion at large rates, the two processes are comparable for charmed mesons, while electromagnetic production will be dominant for bottom mesons. We discuss the possibility of observing the reaction gammagamma(PP) --> R --> gammagamma, and comment on the particular case where R could be a scalar resonance at 650 MeV.

Conjunctival keratoacanthoma

Keratoacanthoma is a rapidly growing skin neoplasia that may stabilize or regress spontaneously. We describe here a case of conjunctival keratoacanthoma and comment about the clinical signs and symptoms and pathological findings.

Quantização de sistemas singulares via formalismo de Hamilton-Jacobi

Pós-graduação em Física - IFT

A new species of Rhinella (Anura: Bufonidae) from Northeastern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caos e termalização na teoria de Yang-Mills-Higgs em uma rede espacial

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Geração digital: uma reflexão sobre as relações da juventude digital e os campos da comunicação e da cultura

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Competing regression models for longitudinal data

The choice of an appropriate family of linear models for the analysis of longitudinal data is often a matter of concern for practitioners. To attenuate such difficulties, we discuss some issues that emerge when analyzing this type of data via a practical example involving pretestposttest longitudinal data. In particular, we consider log-normal linear mixed models (LNLMM), generalized linear mixed models (GLMM), and models based on generalized estimating equations (GEE). We show how some special features of the data, like a nonconstant coefficient of variation, may be handled in the three approaches and evaluate their performance with respect to the magnitude of standard errors of interpretable and comparable parameters. We also show how different diagnostic tools may be employed to identify outliers and comment on available software. We conclude by noting that the results are similar, but that GEE-based models may be preferable when the goal is to compare the marginal expected responses.

Infinite dimensional Lie algebra associated with conformal transformations of the two-point velocity correlation tensor from isotropic turbulence

We deal with homogeneous isotropic turbulence and use the two-point velocity correlation tensor field (parametrized by the time variable t) of the velocity fluctuations to equip an affine space K3 of the correlation vectors by a family of metrics. It was shown in Grebenev and Oberlack (J Nonlinear Math Phys 18:109–120, 2011) that a special form of this tensor field generates the so-called semi-reducible pseudo-Riemannian metrics ds2(t) in K3. This construction presents the template for embedding the couple (K3, ds2(t)) into the Euclidean space R3 with the standard metric. This allows to introduce into the consideration the function of length between the fluid particles, and the accompanying important problem to address is to find out which transformations leave the statistic of length to be invariant that presents a basic interest of the paper. Also we classify the geometry of the particles configuration at least locally for a positive Gaussian curvature of this configuration and comment the case of a negative Gaussian curvature.