Tecnologias digitais na educação matemática de surdos em uma escola pública regular: possibilidades e limites

A introdução das Tecnologias Digitais da Informação e Comunicação (TDIC) em aulas de Matemática para alunos surdos da Educação Básica foi o objeto deste estudo. Na pesquisa, uma turma exclusiva de alunos surdos, em uma escola pública municipal de Belo Horizonte, foi levada ao laboratório de informática para interagir com um objeto de aprendizagem (OA) da Rede Interativa Virtual de Educação do MEC. A investigação atentou para a dinâmica da aula na sala de computadores, as estratégias que pudessem favorecer o uso das TDIC pelos alunos, as ações dos sujeitos neste novo ambiente e possibilidades oferecidas pelo OA utilizado. Os dados foram coletados através de uma ação-pesquisa que contou com um questionário, entrevistas semiestruturadas, grupos focais e observação. O estudo enfocou a questão comunicativa dos surdos e foi fundamentado em discussões sobre a educação inclusiva, as TDIC na educação de alunos com necessidades especiais e a educação Matemática em ambiente de diálogo. O aspecto visual presente no recurso digital se revelou útil para atender às possibilidades perceptivas sensoriais e comunicativas dos alunos surdos. Outros aspectos positivos do uso do OA foram a possibilidade de experimentação e repetição, respeitando o ritmo próprio do aluno, e a presença de diferentes representações da situação matemática proposta, elementos relevantes para o aprendizado desses alunos. Registraram-se o interesse e a motivação dos alunos surdos pelo uso do computador, ainda que se tenha notado também a sua dificuldade em relação aos conteúdos disponibilizados em Língua Portuguesa que, para eles, não é natural. Além disso, o layout do laboratório adotado na escola revelou-se inadequado para as atividades com alunos surdos

Selection from read-only memory with limited workspace

Given an unordered array of $N$ elements drawn from a totally ordered set and an integer $k$ in the range from $1$ to $N$, in the classic selection problem the task is to find the $k$-th smallest element in the array. We study the complexity of this problem in the space-restricted random-access model: The input array is stored on read-only memory, and the algorithm has access to a limited amount of workspace. We prove that the linear-time prune-and-search algorithm---presented in most textbooks on algorithms---can be modified to use $\Theta(N)$ bits instead of $\Theta(N)$ words of extra space. Prior to our work, the best known algorithm by Frederickson could perform the task with $\Theta(N)$ bits of extra space in $O(N \lg^{*} N)$ time. Our result separates the space-restricted random-access model and the multi-pass streaming model, since we can surpass the $\Omega(N \lg^{*} N)$ lower bound known for the latter model. We also generalize our algorithm for the case when the size of the workspace is $\Theta(S)$ bits, where $\lg^3{N} \leq S \leq N$. The running time of our generalized algorithm is $O(N \lg^{*}(N/S) + N (\lg N) / \lg{} S)$, slightly improving over the $O(N \lg^{*}(N (\lg N)/S) + N (\lg N) / \lg{} S)$ bound of Frederickson's algorithm. To obtain the improvements mentioned above, we developed a new data structure, called the wavelet stack, that we use for repeated pruning. We expect the wavelet stack to be a useful tool in other applications as well.Comment: 16 pages, 1 figure, Preliminary version appeared in COCOON-201

Leibnizian, Robinsonian, and Boolean Valued Monads

This is an overview of the present-day versions of monadology with some applications to vector lattices and linear inequalities.Comment: This is a talk prepared for the 20th St. Petersburg Summer Meeting in Mathematical Analysis, June 24-29, 201

Immune Reconstitution Kinetics as an Early Predictor for Mortality using Various Hematopoietic Stem Cell Sources in Children

AbstractThe severity of complications of allogeneic hematopoietic stem cell transplantation (HSCT) is governed mainly by the status of immune reconstitution. In this study, we investigated differences in immune reconstitution with different cell sources and the association between the kinetics of immune reconstitution and mortality. Immunophenotyping was performed every 2 weeks in children who had undergone HSCT between 2004 and 2008 at University Medical Center Utrecht. Lymphocyte reconstitution in the first 90 days after HSCT was studied in relation to mortality in 3 HSCT groups: matched sibling bone marrow (BM) recipients (35 patients), unrelated BM recipients (32 patients), and unrelated cord blood recipients (36 patients). The median age of recipients was 5.9 years (range, 0.1-21 years). The nature and speed of T cell, B cell, and natural killer (NK) cell reconstitution were highly dependent on the cell source. In the first 90 days after HSCT, faster B cell and NK cell reconstitution and delayed T cell reconstitution were shown in unrelated cord blood recipients compared with matched sibling BM and unrelated BM recipients. Of the lymphocyte subsets investigated, a large number of NK cells and a more rapid CD4+ immune reconstitution over time, resulting in sustained higher CD4+ counts, were the only predictors of a lower mortality risk in all cell sources. The final model showed that during the first 90 days, patients with an area under the CD4+ cell receiver- operating curve of >4,300 cells/day and no peak in CD4+ cell counts had the highest likelihood of survival (hazard ratio for mortality, 0.2; 95% confidence interval, 0.06-0.5). Our data indicate that CD4+ kinetics may be used to identify patients at greatest risk for mortality early after HSCT

The spectral shift function and spectral flow

This paper extends Krein's spectral shift function theory to the setting of semifinite spectral triples. We define the spectral shift function under these hypotheses via Birman-Solomyak spectral averaging formula and show that it computes spectral flow.Comment: 47 page