How to drag with a worn-out mouse? Searching for social justice through collaboration

We consider what a concern for social justice in terms of social inclusion might mean for teacher education, both practising and prospective, with particular reference to the use of information and communication technology (ICT) in mathematics education taking place at a borderland school. Our discussion proceeds through the following steps: (1) We explore what a borderland position might denote to address what social inclusion might mean. (2) We consider the significance of mathematics education and the use of ICT for processes of social inclusion. (3) We briefly refer to the Interlink Network, as many of our observations emerge as reflections on this project. (4) We present different issues that will be of particular importance with respect to teacher education if we want to establish a mathematics education for social inclusion. These issues concern moving away from the comfort zone, establishing networks, identifying new approaches, moving beyond prototypical research, and getting in contact. This brings us to (5) final considerations, where we return to the notion of social justice. © Springer Science+Business Media B.V. 2009.

A aprendizagem matemática em uma posição de fronteira: Foregrounds e intencionalidade de estudantes de uma favela brasileira

In a large metropolis, students from different neighbourhoods can experience very different life opportunities. This can influence their attitude towards schooling and learning, including the learning of mathematics. We interviewed a group of six students from a favela in a large city in the interior of the state of São Paulo in Brazil. We invited the students to look into their future and explore whether or not there could be learning motives that linked mathematics in school to possible out-of-school practices, either in terms of possible future jobs or further studies. We identified some themes in the students' descriptions of their experiences. The first theme is discrimination. The students feel discriminated against due to the fact that they come from a poor neighbourhood. They fear being trapped in some stereotypes. The second theme is escape. There is a strong motivation to begin a new life away from the favela. A third theme concerns the obscurity of mathematics. It seems clear to everybody that education is relevant to ensure a change in life. However, the mathematics lessons do not provide any clues regarding how mathematics might function is this respect. The fourth theme is uncertainty with respect to the future. The students could easily formulate almost unattainable aspirations, while reality might impose some very heavy limitations. In this article we introduce a theoretical framework for discussing the relation between favela students' life conditions in relation to their educational experiences and opportunities. Students' intentions for learning are related to their foregrounds, that is, how they perceive their future possibilities, as made evident to them by their social environment. Students in a favela could experience what we call a borderland position, a relational space where individuals meet their social environment and come to terms with the multiple choices that cultural and economic diversity make available to them.

The position effect of structural Eucalyptus round timber on the flexural modulus of elasticity

A madeira roliça possui grande emprego nas construções civis, desempenhando a função de vigas, colunas, fundações, postes para distribuição de energia elétrica, entre outras, apresentando a vantagem de não ser processada, como é o caso da madeira serrada. O projeto envolvendo elementos roliços requer, além de outras variáveis estruturais, o conhecimento do módulo de elasticidade. No Brasil, os documentos normativos que tratam da determinação das propriedades de rigidez e resistência para peças roliças de madeira estão em vigência há mais de vinte anos sem revisão técnica. A madeira roliça, por geralmente possuir eixo com curvatura não nula, pode apresentar, segundo a posição da peça no ensaio de flexão, valores diferentes do módulo de elasticidade. Este trabalho tem como objetivo analisara influência da posição de peças roliças de madeira de Eucalyptus grandis na determinação do módulo de elasticidade na flexão. O ensaio de flexão utilizado é o de três pontos, sendo cada peça avaliada em duas posições distintas, definidas mediante o giro da seção transversal em torno do eixo. Os resultados encontrados indicam a necessidade do ensaio de flexão em, pelo menos, duas posições distintas da peça.

Lumber quality of Eucalyptus grandis as a function of diametrical position and log steaming

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

Position-dependent effective mass Dirac equations with PT-symmetric and non-PT-symmetric potentials

We present a new procedure to construct the one-dimensional non-Hermitian imaginary potential with a real energy spectrum in the context of the position-dependent effective mass Dirac equation with the vector-coupling scheme in 1 + 1 dimensions. In the first example, we consider a case for which the mass distribution combines linear and inversely linear forms, the Dirac problem with a PT-symmetric potential is mapped into the exactly solvable Schrodinger-like equation problem with the isotonic oscillator by using the local scaling of the wavefunction. In the second example, we take a mass distribution with smooth step shape, the Dirac problem with a non-PT-symmetric imaginary potential is mapped into the exactly solvable Schrodinger-like equation problem with the Rosen-Morse potential. The real relativistic energy levels and corresponding wavefunctions for the bound states are obtained in terms of the supersymmetric quantum mechanics approach and the function analysis method.

On the Dirac equation with PT-symmetric potentials in the presence of position-dependent mass

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Extension of PT-symmetric quantum mechanics to the Dirac theory with position-dependent mass

We present a new method to construct the exactly solvable PT-symmetric potentials within the framework of the position-dependent effective mass Dirac equation with the vector potential coupling scheme in 1 + 1 dimensions. In order to illustrate the procedure, we produce three PT-symmetric potentials as examples, which are PT-symmetric harmonic oscillator-like potential, PT-symmetric potential with the form of a linear potential plus an inversely linear potential, and PT-symmetric kink-like potential, respectively. The real relativistic energy levels and corresponding spinor components for the bound states are obtained by using the basic concepts of the supersymmetric quantum mechanics formalism and function analysis method. (C) 2007 Elsevier B.V. All rights reserved.

Two-dimensional position-dependent massive particles in the presence of magnetic fields

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Wigner distribution for a class of isospectral position-dependent mass systems

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Comparison of Macintosh and AirtraqTM laryngoscopes in obese patients placed in the ramped position

This study compared intubation conditions produced by the Macintosh and AirtraqTM laryngoscopes when used in obese patients in the ramped position. One hundred and thirty-two patients having bariatric surgery were placed in the ramped position and randomly assigned to have their tracheas intubated using either the Macintosh (n = 64) or an Airtraq (n = 68) laryngoscope. Mean (SD) intubation times were 37 (23) s and 14 (3) s for Macintosh and Airtraq, respectively (p < 0.0001). Compared with the Macintosh laryngoscope, the Airtraq laryngoscope provided an improved vocal cord view as assessed by the Cormack and Lehane score (number of patients with Cormack-Lehane scores of 1/2/3/4/37/20/4/3 for the Macintosh, and 65/3/0/0 for the Airtraq laryngoscopes, p < 0.0001). One patient in the Macintosh group had a failed intubation and intubation was achieved with the Airtraq. For obese patients in ramped position, Airtraq affords faster tracheal intubation than the Macintosh laryngoscope.

Technique for Indexing an Immediate Loading Implant Position for a Provisional Restoration

The transfer of an intraoral implant position to the cast for an immediate loading implant is an important step and may be difficult to achieve with commonly used transfer and impression methods. Thus, the purpose of this report is to describe a technique for the use of a surgical template to transfer the implant position for fabrication of a provisional restoration. This technique simplifies the procedure, eliminates the need for taking an impression, avoids surgical site contamination, and maintains an adequate emergence profile during fabrication of the definitive restoration. An indexing technique for transferring the position of the implant from the treated surface after extraction is described.

TAXONOMIC POSITION of GUIRATINGIA MENDESI (MEGADESMIDAE) and THE EVOLUTION of PERMIAN ENDEMIC BIVALVE FAUNA of THE PARANA BASIN, BRAZIL

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

Multiple nucleolus organizer regions in Leptodactylus mystacinus (Amphibia, Anura) and comments on its systematic position in the L fuscus group based on cytogenetic and molecular analyses

Specimens of Leptodactylus mystacinus from Brazil were karyotyped with conventional and differential staining. The 2n = 22 karyotype is similar to that found for the majority of the Leptodactylus, the karyotypic conservatism also confirmed by the similarity of the replication banding patterns with those previously described. L. mystacinus has a small amount of C-banded heterochromatin, located mainly at the centromeres, although telomeric or interstitial bands have also been noticed. With DA/CMA(3) some chromosome regions showed slightly bright fluorescence, and with DA/DAPI, no particular AT-rich repetitive region was observed. Silver staining showed an extensive inter- and intraindividual variation in the number and position of Ag-positive regions, in 1p, 4p, 8p, 8q, and 11p. Nevertheless, FISH using rDNA probes confirmed only the signals on the short arms of chromosomes 4 and 8 as true NORs. The remaining silver stained regions are probably due to the heterochromatin with some affinity to the Ag-staining. Phylogenetic analysis based on partial cytochrome b sequence revealed that L. mystacinus forms a basal branch, so that the presence of multiple NORs in pairs 4 and 8 in this species indicates an autapomorphy.