Análise Narrativa em Trabalhos de História da Educação Matemática: algumas considerações

This paper presents some reflections on the use of narrative analysis as a possible approach to study the History of (Mathematics) Education, mainly to interpret historical situations and biographical data. Its perspective is linked to Walter Benjamin's ideas about the figure of the narrator and how the dialogue between narrator and historian can be seen. Following the perspective of another author, Benedito Nunes, we try to establish relations among narratives, fiction and historiography, also highlighting the ideas of Jorge Larrosa regarding the transmission of experiences. Finally, our focus is turned to Antonio Bolivar and his alternative statements about why and how analysis of investigations, in which narratives are the main source of data, can be done.

História na Educação Matemática – um estudo sobre trabalhos publicados no Brasil nos últimos cinco anos

In this paper we report a study on research in the field of History in Mathematics Education conducted in Brazil in the last five years. We evaluate studies that are theoretical or report experiences on the support found in history that can contribute to the situations of teaching and learning of mathematics, based on the Proceedings of Seminarios Nacionais de Historia da Matematica and Encontros Luso-Brasileiros de Historia da Matematica. Examining the interests, directions and focus of research in the field, we found that the vast majority of studies address specific issues of History of Mathematics, and the number of studies on History in Mathematics Education is still very low. We note that, in the last five years, the arguments in favor of the teaching potential of the History of Mathematics, which is very present in the speech of teachers and managers of public education, has not yet been materialized in experiments or investigations to promote this link effectively.

Lesões do trato gastrointestinal na síndrome da imunodeficiência adquirida: estudo de 45 necrópsias consecutivas.

This study was designed to evaluate retrospectively the frequency and etiology of the gastrointestinal (GI) lesions in 45 consecutive necropsies of adult patients with Acquired Immunodeficiency Syndrome (AIDS). Gross descriptions and histological sections of the GI tract, from mouth to anus, were reviewed. The slides were H&E stained, and when necessary special stains and immunohistochemical methods were also employed. There were lesions in GI tract in 37 (82.3%) patients; the mouth was the segment most frequently involved (73.3% of the cases), followed by the colon (55.5%). Multiple lesions occurred in 17 (37.7%) cases. Cytomegalovirus caused colonic lesions in 35.7% of the cases. Candidiasis was observed in 26.6% mainly in the mouth and herpes simplex (8.8%) was the important agent of esophageal lesions. Oral hairy leukoplasia associated with HPV was found in 16 (35.5%) cases. Neoplasia was diagnosed in 7 (15.5%) cases: four Kaposi's sarcoma, two anal intramucosal carcinomas and one gastric lymphoma. Our data confirm the high frequency and variety of GI tract alterations in AIDS.

Algorithms for network piecewise-linear programs: A comparative study

Piecewise-Linear Programming (PLP) is an important area of Mathematical Programming and concerns the minimisation of a convex separable piecewise-linear objective function, subject to linear constraints. In this paper a subarea of PLP called Network Piecewise-Linear Programming (NPLP) is explored. The paper presents four specialised algorithms for NPLP: (Strongly Feasible) Primal Simplex, Dual Method, Out-of-Kilter and (Strongly Polynomial) Cost-Scaling and their relative efficiency is studied. A statistically designed experiment is used to perform a computational comparison of the algorithms. The response variable observed in the experiment is the CPU time to solve randomly generated network piecewise-linear problems classified according to problem class (Transportation, Transshipment and Circulation), problem size, extent of capacitation, and number of breakpoints per arc. Results and conclusions on performance of the algorithms are reported.

Abordagem initial do paciente com mielopatia aguda não compressiva

Acute myelopathy are characterized by spinal cord dysfunction, developing sensitive, motor and autonomic signs and symptons. Since they are relatively rare, there are some difficulties to early diagnosis and to the beginning of the treatment. So, literature was reviewed to describe the main aetiologies of acute non compressive myelopathy: 1) demyelinating diseases; 2) systemic disease; 3) parainfectious; 4) delayed radiation myelopathy; 5) vascular myelopathy; 6) idiopatic and 7) vitamin B12 deficiency. Besides, we suggest an algorithm to initial approach of these patients and further aethiologic investigation. © Copyright Morelra Jr. Editora.

Limit cycles for singular perturbation problems via inverse integrating factor

In this paper singularly perturbed vector fields Xε defined in ℝ2 are discussed. The main results use the solutions of the linear partial differential equation XεV = div(Xε)V to give conditions for the existence of limit cycles converging to a singular orbit with respect to the Hausdorff distance. © SPM.

Geração de padrões de corte n-grupos para a indústria moveleira

Neste artigo são apresentadas propostas de soluções para o problema de geração de padrões de corte n-grupos para o corte da matéria-prima na indústria moveleira. Este problema NP-difícil aparece em diversos outros processos industriais que incluem o corte de painéis retangulares grandes de tamanho padrão em retângulos menores. O planejamento dos cortes é um aspecto importante do planejamento da produção nestas indústrias, pois efeitos negativos tais como o perda de matériaprima e tempo de preparo da máquina de corte podem ser minimizados, diminuindo assim os custos de produção. É estudada a eficiência de modelos lineares inteiros para resolver o problema do corte guilhotinado bidimensional propostos em [33,34], bem como o seu uso na geração de colunas para o problema de corte de estoque. São usados dados reais de uma fábrica de móveis de pequeno porte característica do pólo moveleiro de Votuporanga/SP. Os resultados obtidos indicam que as estratégias propostas geram perdas dentro dos requisitos exigidos pela fábrica. © SPM.

Educaçãdo matemática na realidade do ciberespaço - Que aspectos ontológicos e científicos se apresentam?

The question that leads this article is What is this virtual space in the on-line mathematics education process? We focus on the question of the real and virtual as issues taken as components of cyberspace. We investigate these notions in the history of philosophy, looking to Granger to find their meaning, to enable us to understand them and fit them into the sphere of Mathematics Education. This theoretical-philosophical article, then, claims that the virtuality of cyberspace is supported by the computer screen, built by the unification of the sciences (mathematics), technology and its applications. Software and the actions taken by Internet users update the capability of these programs in a variety of characteristics and possibilities such as space-time flow interconnections as well as during the mathematics education process.