Collectives of humans-with-media in mathematics education: Notebooks, blackboards, calculators, computers and ... notebooks throughout 100 years of ICMI

The main aim of this study was to present evidence of the ways in which different media have conditioned and dramatically reorganized education, in general, and mathematics education, in particular. After an introduction of the theme, we discuss the epistemological perspective that provides the foundation for our analysis: the notion of humans-with-media. Then, we briefly illustrate how the medium is related to the scientific production of mathematical knowledge. We take a detour into the world of art to examine how devices and instruments have historically been associated with the production of mathematical knowledge. Then, we review studies on the history of education to show how traditional media were introduced into schools and have influenced education. In particular, we examine how devices such as blackboards and notebooks, which were novelties a 100 years ago, came to be accepted in schools and the mathematical activities that were promoted with their use. Finally, we discuss how information technology has changed education and how the Internet may have an impact on mathematics education comparable to that of the notebook over a century ago. © FIZ Karlsruhe 2009.

Financing for development and middle income-countries: new challenges

Spanish version avalilable at the Library

Landscape reshaping of the asylum of san francisco de paula, located in jaboticabal, Sao Paulo State, Brazil

It is a commonly known fact that there are elderly who have no family or who do not receive any kind of help from their relatives, as the family does not normally have good financial conditions to help them. These elderly live in private or public shelters and generally, they do not have enough money to cover all the necessary costs, and are forced to survive from donations. Those shelters are based, primarily, on nutrition and health. Leisure and wellbeing are usually treated with little attention, but it could be obtained in a simple and effective way: green areas, which normally exist at the site, are often misused, so they can become rest areas through simple landscape projects. It is important to mention that a garden is not just a beautiful place, but it becomes important for the daily life of older people. The objective of this work was to study the need for contemplative leisure and labor in order to improve the life quality of the elderly that live at the San Francisco de Paula Asylum, in Jaboticabal City, Sao Paulo State, Brazil. In this study, a topographic and a photographic survey was conducted and an analysis of the local ground was done. The preferences of the employees and the visitors of the building were also recorded, as well as the critical points of the area. After this primary analysis, the landscape planning was done, with the help of the AutoCAD 2004 software, prioritizing the use of plants that are not dangerous and that are easy maintained. An orchid nursery was also created in order to provide weekly workshops of orchid cultivation.

Small- and medium-sized enterprises' restructuring in a context of transition: a shared process: inter-player effects on efficient boundary choice in the Argentine manufacturing sector

Includes bibliography

Regional interdependencies and macroeconomic crises: notes on MERCOSUR

Includes bibliography

A emergência da noção de comportamento simbólico em neuropsicopatologia

In this article, we present the notion of symbolic behavior in accordance with neuropsychopathology research from the first decades of the past century, carried out particularly in the context of aphasia research. The guiding axis was the presence of this notion in the first work by Merleau-Ponty, The structure of behavior. Based on research by Gelb and Goldstein, the philosopher takes ownership of the semantics of the symbolic and characterizes human corporality based on its capacity to move beyond the immediate nature of the experienced situations. We also show that the circumscription of symbolic behavior was conditioned by theoretical-methodological changes that permitted the passage from localizationist conceptions to globalist attitudes in view of pathological events of cerebral origin.

Expenditures, investment and financing for sustainable development in Brazil

Includes bibliography

Blood cells attachment after root conditioning and PRP application: An in vitro study

Aim: Root conditioning is aimed at smear layer removal and at dental matrix collagen exposure, which may promote periodontal regeneration. This in vitro study assessed smear layer removal, collagen fiber exposure and the influence of PRP (platelet-rich plasma) application on adhesion of blood cells to the root surface using scanning electron microscopy (SEM). Materials and methods: Scaled root samples (n = 160) were set in five groups and conditioned with: group I - control group (saline solution); group II (EDTA 24%); group III (citric acid 25%); group IV (tetracycline hydrochloride 50 mg/ml); group V (sodium citrate 30%). Eighty samples were assessed using the root surface modification index (RSMI). The other eighty samples were set in two groups. The first group (n = 40) received PRP gel application with a soft brush and the second group (n = 40) received PRP application and then a blood drop. The fibrin clot formation was assessed in the first group and the blood cells adhesion was assessed in the second group using the BEAI (blood elements adhesion index). A previously trained, calibrated, and blind examiner evaluated photomicrographs. Statistical analysis was performed using the Kruskal-Wallis's and Dunn's tests. Results: Group III attained the best results for RSMI and BEAI. Moreover, it was the only group showing fibrin clot formation. Conclusion: Citric acid was the most efficient conditioner for smear layer removal, collagen fiber exposure and blood cell adhesion. Moreover, it was the only group showing fibrin clot formation after PRP application. Clinical significance: This study demonstrated that root conditioning followed by PRP application may favor blood cell adhesion on root surface which may optimize periodontal healing.

Concentrações séricas de aspartato aminotransferase e creatinoquinase e concentrações plasmáticas de lactato em equinos da raça Mangalarga Marchador após exercício físico

The aim of this study was evaluate the influence of physical exercise (marcha gait) on serum values of CK and AST and plasmatic values of lactate in Mangalarga Marchador horses trained in Espirito Santo, Brazil. Serum and plasma samples were obtained from 15 horses in four different moments: rest (T0), 5 minutes (T1), 30 minutes (T2) and 2 hours (T3) after the exercise. Lactate analysis revealed values of 1.02 ± 0.41 mmol/L, 2.73 ± 2.43 mmol/L, 1.89 ± 1.24 mmol/L and 1.31 ± 0.60 mmol/L, respectively at T0, T1, T2 and T3. When evaluating AST, the results recorded in T0, T1, T2 and T3 were, respectively, 189.3 ± 56.0 UI/L, 223.9 ± 53.5 UI/L, 186.8 ± 25.8 UI/L and 193.9 ± 44.7 UI/L. Finally, the CK at moments T0, T1, T2 and T3 were, respectively, 113.4 ± 56.3 UI/l, 144.1 ± 70.9 UI/L, 143.0 ± 81.0 UI/L and 173.1 ± 128.0 UI/L. The results showed that marcha gait leaded to significantly increased in plasma lactate and did not alter serum AST and CK, suggesting that the equines used were conditioned to the physical exercised imposed.

Effect of experimental photopolymerized coatings on the hydrophobicity of a denture base acrylic resin and on Candida albicans adhesion

Objective: This study investigated the effect of experimental photopolymerized coatings, containing zwitterionic or hydrophilic monomers, on the hydrophobicity of a denture base acrylic resin and on Candida albicans adhesion. Methods: Acrylic specimens were prepared with rough and smooth surfaces and were either left untreated (control) or coated with one of the following experimental coatings: 2-hydroxyethyl methacrylate (HE); 3-hydroxypropyl methacrylate (HP); and 2-trimethylammonium ethyl methacrylate chloride (T); and sulfobetaine methacrylate (S). The concentrations of these constituent monomers were 25%, 30% or 35%. Half of the specimens in each group (control and experimentals) were coated with saliva and the other half remained uncoated. The surface free energy of all specimens was measured, regardless of the experimental condition. C. albicans adhesion was evaluated for all specimens, both saliva conditioned and unconditioned. The adhesion test was performed by incubating specimens in C. albicans suspensions (1 × 10 7 cell/mL) at 37 °C for 90 min. The number of adhered yeasts were evaluated by XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-5-[{phenylamino} carbonyl]-2H-tetrazolium-hydroxide) method. Results: For rough surfaces, coatings S (30 or 35%) and HP (30%) resulted in lower absorbance values compared to control. These coatings exhibited more hydrophilic surfaces than the control group. Roughness increased the adhesion only in the control group, and saliva did not influence the adhesion. The photoelectron spectroscopy analysis (XPS) confirmed the chemical changes of the experimental specimens, particularly for HP and S coatings. Conclusions: S and HP coatings reduced significantly the adhesion of C. albicans to the acrylic resin and could be considered as a potential preventive treatment for denture stomatitis. © 2012 Elsevier Ltd.

Social sciences and social reality in Central America

Includes bibliography

Open regionalism and economic integration

Includes bibliography

The restructuring of the Brazilian industrial groups between 1980 and 1993

Includes bibliography

Major macroeconomic disturbances, expectations and policy responses

Includes bibliography

The Latin American social agenda in the year 2000

Includes bibliography