Uma abordagem sobre o conceito de função no ensino médio.

O ensino do conceito de função tem sido um dos grandes desafios para o docente, em particular durante a primeira série do ensino Médio. Tal assunto constitui-se, para o aluno, um obstáculo cognitivo, contribuindo para o distanciamento da Matemática. A carga de abstração contida no conceito de função e o formalismo exagerado dos livros didáticos contribuem para que o professor não obtenha êxito durante a abordagem deste assunto. Surge, assim, a necessidade de conhecer previamente a abordagem e o método utilizado pelo autor do livro didático adotado como livro texto, sendo indispensável a leitura crítica por parte do professor. Neste trabalho propõe-se uma sequência didática para o ensino do conceito e das propriedades de Função. Nesse sentido, criou-se um roteiro de análise adaptado a partir de critérios utilizados no guia do Plano Nacional do Livro Didático (PNLD) do ano de 2012, o qual foi utilizado para verificar a abordagem metodológica praticada durante a apresentação da definição de função utilizada em livros didáticos do primeiro ano do ensino médio.Teaching the concept of function has been a major challenge for the teachers, particularly during the first year of high school. This issue constitutes, for the student, a cognitive obstacle what contributes to the detachment of mathematics by the students. The abstraction charge contained in the concept of function and the exaggerated formalism in the textbooks does not contribute to the success of the teacher when approaching this issue. It raises the need to know beforehand the approach and method used by the author being essential the analysis of the textbooks by the teacher. Given this fact, this paper proposes a didactic sequence for teaching the concept of functions. It was created an adapted analysis script based on the criteria used in the Plano Nacional do Livro Didático (PNLD) of 2012, in order to examine the methodological approach practiced during the presentation of the definition of function used by teachers in the first year of high school textbooks.Cape

The orbit space of groupoids whose C∗C^*-algebras are GCR

Let $G$ be second countable locally compact Hausdorff groupoid with a continuous Haar system. We remove the assumption of amenability in a theorem by Clark about GCR groupoid $C^*$-algebras. We show that if the groupoid $C^*$-algebra of $G$ is GCR then the orbits of $G$ are locally closed.Comment: 1

Uncovering the Signaling Landscape Controlling Breast Cancer Cell Migration Identifies Novel Metastasis Driver Genes

Ttriple-negative breast cancer (TNBC) is an aggressive and highly metastatic breast cancer subtype. Enhanced TNBC cell motility is a prerequisite of TNBC cell dissemination. Here, we apply an imaging-based RNAi phenotypic cell migration screen using two highly motile TNBC cell lines (Hs578T and MDA-MB-231) to provide a repository of signaling determinants that functionally drive TNBC cell motility. We have screened ~4,200 target genes individually and discovered 133 and 113 migratory modulators of Hs578T and MDA-MB-231, respectively, which are linked to signaling networks predictive for breast cancer progression. The splicing factors PRPF4B and BUD31 and the transcription factor BPTF are essential for cancer cell migration, amplified in human primary breast tumors and associated with metastasis-free survival. Depletion of PRPF4B, BUD31 and BPTF causes primarily down regulation of genes involved in focal adhesion and ECM-interaction pathways. PRPF4B is essential for TNBC metastasis formation in vivo, making PRPF4B a candidate for further drug developmen

Low fertility and the risk of type 2 diabetes in women

BACKGROUND: Fertility problems are frequently followed by early menopause, and early menopause has been associated with increased risk of type 2 diabetes (T2D). Thus far, it is unknown whether low fertility is independently associated with future T2D risk. METHODS: We assessed the association between measures of low fertility and T2D in the Prospect-European Prospective Investigation into Cancer and Nutrition (EPIC) cohort of 17 357 Dutch women, aged 49-70 years at baseline using Cox proportional hazards models, adjusted for various confounders. To investigate whether BMI and waist circumference influence the observed associations, analyses were additionally adjusted for these variables. RESULTS: At baseline, 332 women had T2D. During a mean follow-up of 9.1 +/- 3.6 years, 535 T2D cases occurred. Out of 15 707 Prospect-EPIC women who wanted to get pregnant, 1940 consulted a physician for fertility problems and 700 remained childless. No relation was found between consulting a physician for fertility problems or nulliparity and T2D risk. Of all women who wanted to get pregnant, 3946 (25.1%) had one or more miscarriages, with an average of 1.4 (+/- 0.9) miscarriages and a maximum of 10 miscarriages. Women who had one or more miscarriage showed the same risk for T2D as women who had no miscarriage. Also, none of the other measures of low fertility were associated with increased risk for T2D. CONCLUSIONS: Generally, measures of low fertility were not independently associated with a risk of T2D in a cohort of 17 357 Dutch women

Quality of reporting of randomized controlled trials in polycystic ovary syndrome

Background: Inadequate reporting of randomized controlled trials (RCTs) is associated with biased estimates of treatment effects. The reporting quality of RCTs involving patients with polycystic ovary syndrome (PCOS) is unknown. The purpose of this study was to assess the reporting quality of RCTs involving patients with PCOS using a standardized tool based on the Consolidated Standards of Reporting Trials (CONSORT) statement. Methods: We searched PubMed database for English-language RCTs involving patients with PCOS. Quality of reporting was assessed using a 24-item questionnaire based on the revised CONSORT checklist. Reporting was evaluated overall, and for pre- and post-CONSORT periods. RCTs on PCOS associated with fertility and non-fertility disturbances were also evaluated separately. Results: Nine of the 24 items were reported in less than 50% of the studies, while a significant improvement (P < 0.05) was detected in 12 of 24 items (50%) over the two CONSORT periods. The RCTs on PCOS with reference to fertility seem to have adhered better to CONSORT statement than RCTs not associated to fertility. Conclusion: There is empirical evidence of suboptimal reporting quality of RCTs in PCOS. Endorsement of the CONSORT statement may optimize the reporting quality and enhance the validity of research