An encounter between Paulo Freire and mathematics education: Maria do Carmo Domite instigated by Régis Forner

A professora Maria do Carmo Santos Domite conta ao mestrando da educação matemática Régis Forner sua vivência junto ao educador Paulo Freire –um dos maiores ícones da educação brasileira– em especial, durante sua gestão na Secretaria Municipal de Educação de São Paulo. De modo geral, Domite coloca sua reflexão na busca de Freire em situar a ação educativa na cultura do educando, no sentido de considerar/respeitar a cultura que cada um traz dentro de si –finalidades que uma professora e um professor que vêem a educação como uma prática libertadora devem perseguir. Paulo Freire publicou mais de 30 obras. A mais famosa Pedagogia do Oprimido foi publicada primeiramente em inglês em 1970 e, no Brasil, somente em 1974, hoje na 50ª edição. Freire foi exilado político de 1964 a 1980, residiu em vários países onde também contribuiu para a discussão das políticas educacionais locais. Domite, professora da Faculdade de Educação da Universidade de São Paulo, vem desenvolvendo seus estudos e pesquisas em Etnomatemática sempre considerando o potencial de levar em conta a cultura dos educandos nos processos educacionais. Esta entrevista surge de uma ramificação da dissertação de mestrado de Régis Forner (Pontifícia Universidade Católica de Campinas), no qual ele buscava estabelecer as relações e influências das ideias e teorizações de Paulo Freire na Educação MatemáticaEn este documento la profesora Maria do Carmo Santos Domite entrevista al estudiante de Máster en Educación Matemática, Régis Forner, sobre las experiencias que vivió junto a uno de los mayores iconos de la educación brasileña, Paulo Freire, en especial, durante su permanencia en la Secretaría Municipal de Educación de São Paulo. Domite reflexiona en torno a la intención de Freire de situar la acción educativa en la cultura de los estudiantes, es decir, considerando y respetando la cultura que cada estudiante trae consigo y entendiendo que la meta de la Educación es perseguir la práctica de la libertad. Paulo Freire publicó más de 30 obras literarias. La más famosa es la Pedagogía del Oprimido, publicada inicialmente en Inglés en 1970, más tarde puesta a libre disposición en Brasil en 1974, y que actualmente se encuentra en su 50ª edición. Paulo Freire, exiliado entre 1964 y 1980, vivió en varios países desde donde también contribuyó al diálogo y el desarrollo de las políticas educativas locales. La profesora Domite ha llevado a cabo estudios e investigaciones en Etnomatemáticas, siempre preocupada por entender el potencial que significa considerar la cultura de los estudiantes en los procesos educativos. Esta entrevista surge de una ramificación de la tesis de Régis Forner (PUC-Campinas, en São Paulo), en la que Régis trató de establecer la relación y la influencia de las ideas y las teorías de Paulo Freire en la Educación MatemáticaProfessor Maria do Carmo Santos Domite talks to the mathematics education master student Régis Forner about her experiences along with Paulo Freire –one of the most note-worthy personalities in the history of Brazilian education– especially, while his tenure at the São Paulo Municipal Secretary of Education. In general, Domite places her reflection on Freire’s search in locating the educational action in the student's culture, that is, considering and respecting the culture that each student brings inside themselves – goals that a teacher who see education as a practice of freedom should pursue. Paulo Freire published more than 30 literary works. The most famous one is the Pedagogy of the Oppressed, initially published in English in 1970, later released in Brazil only in 1974 and it is currently in its 50th edition. Exiled between 1964 and 1980, Paulo Freire lived in several countries where he also contributed to the dialogue and development of the local educational policies. Domite, Professor of Education of the University of São Paulo has been developing her studies and researches in Ethnomathematics, always concerned about understanding the potential of taking in account the culture of the students in educational processes. This interview emerges from one ramification of the thesis of Régis Forner (PUC-Campinas in São Paulo State), in which Régis sought to establish the relationship and influence of ideas and theorizations from Paulo Freire in Mathematics Educatio

Podoconiosis in Ethiopia. A pilot study to improve the management of Lymphedema.

Podoconiosis is a non-infectious cause of lymphedema, frequent in Africa. The aim of this study is to implement the management of lymphedema secondary to podoconiosis in a rural hospital in Southern Ethiopia. A call for donation of compression garments was made in Spain, to give any used and retired garment among lymphedema patients. The working plan was to train the staff in the lymphatic system, the causes of lymphedema, prevention strategies, skin care, intensive treatment and maintenance at long-term, Decongestive lymphatic treatment of the patients affected from podoconiosis and the adaptation of the donated garments for maintenance phase. Fifteen patients were treated with 10 sessions of Decongestive Lymphatic Therapy (DLT) consisting of Manual Lymphatic Drainage and multilayer bandages. The Percentage of Volume Reduction was 11.3% (95%CI: 8.8-13.9). Fifty percent of the patients showed an increase of the volume of lymphedema as they did not comply with the compression treatment. This pilot study has had good results in helping lymphedema management in Southern Ethiopia. The donation of used garments by chronic patients can be a feasible and effective step to improving the maintenance phase of patients with lymphedema in places with limited resources

From Davydov solitons to decoherence-free subspaces: self-consistent propagation of coherent-product states

The self-consistent propagation of generalized $D_{1}$ [coherent-product] states and of a class of gaussian density matrix generalizations is examined, at both zero and finite-temperature, for arbitrary interactions between the localized lattice (electronic or vibronic) excitations and the phonon modes. It is shown that in all legitimate cases, the evolution of $D_{1}$ states reduces to the disentangled evolution of the component $D_{2}$ states. The self-consistency conditions for the latter amount to conditions for decoherence-free propagation, which complement the $D_{2}$ Davydov soliton equations in such a way as to lift the nonlinearity of the evolution for the on-site degrees of freedom. Although it cannot support Davydov solitons, the coherent-product ansatz does provide a wide class of exact density-matrix solutions for the joint evolution of the lattice and phonon bath in compatible systems. Included are solutions for initial states given as a product of a [largely arbitrary] lattice state and a thermal equilibrium state of the phonons. It is also shown that external pumping can produce self-consistent Frohlich-like effects. A few sample cases of coherent, albeit not solitonic, propagation are briefly discussed.Comment: revtex3, latex2e; 22 pages, no figs.; to appear in Phys.Rev.E (Nov.2001

The noise performance of a high-speed capacitive-sensor interface based on a relaxation oscillator and a fast counter

This paper presents the analysis and experimental results on the noise performances of a capacitive-sensor interface. The interface is able to measure low capacitance values in the order of picofarads and is implemented with a simple relaxation oscillator, a fast counter, and a microcontroller. The goal is to find the criteria to implement a low-noise system, so that, even with a short measuring time, low noise can be obtained. Experimental results are performed in order to prove the validity of the theoretical analysis. The achieved resolution, with a measuring time of 20 ms, was better than 14.2 /spl times/ 10/sup -7/ for the measurement of a capacitance value of 2.2 pF.Peer Reviewe

Production of n-propyl acetate by reactive distillation : experimental and theoretical study

First steps of the development of a catalytic reactive distillation process for the production of n-propyl acetate based on experiments and simulations are proposed. The kinetics for homogeneously (sulphuric acid) and heterogeneously (Amberlyst 15) catalysed reaction were investigated and the constants for a pseudo-homogeneous model are presented. Pilot plant experiments were performed using a homogeneous strong acid catalyst in a packed column. A top-column decanter is used to withdraw the aqueous phase and to reflux the organic phase. Simulation results are in good agreement with experimental data. Thermodynamics nonidealities are taken into account using VLE and LLE NRTL interaction parameters. Alcohol conversion and n-propyl acetate purity may be dramatically increased just by adding to the pilot plant a stripping section in an additional column: six different configurations are identified to achieve such a production. The startup is studied in order to determine the best strategy to achieve steady-state conditions. The strong influence of the composition of the initial charging in the decanter can be seen and an initial charging of the two-phase top product leads to the fastest startup

Exploring the role of electrode microstructure on the performance of non-aqueous redox flow batteries

Redox flow batteries are an emerging technology for long-duration grid energy storage, but further cost reductions are needed to accelerate adoption. Improving electrode performance within the electrochemical stack offers a pathway to reduced system cost through decreased resistance and increased power density. To date, most research efforts have focused on modifying the surface chemistry of carbon electrodes to enhance reaction kinetics, electrochemically active surface area, and wettability. Less attention has been given to electrode microstructure, which has a significant impact on reactant distribution and pressure drop within the flow cell. Here, drawing from commonly used carbon-based diffusion media (paper, felt, cloth), we systematically investigate the influence of electrode microstructure on electrochemical performance. We employ a range of techniques to characterize the microstructure, pressure drop, and electrochemically active surface area in combination with in-operando diagnostics performed in a single electrolyte flow cell using a kinetically facile redox couple dissolved in a non-aqueous electrolyte. Of the materials tested, the cloth electrode shows the best performance; the highest current density at a set overpotential accompanied by the lowest hydraulic resistance. We hypothesize that the bimodal pore size distribution and periodic, well-defined microstructure of the cloth are key to lowering mass transport resistance

The floating capacitor as a differential building block

This paper analyzes the advantages and limitations of using the floating- (or flying-) capacitor technique as a building block with differential input and either differential or single-ended output to implement voltage amplifiers, multiplexers, and coherent amplitude demodulators. Theoretical analysis, supported by experimental results, shows that the fully differential configuration has a better common-mode rejection ratio (CMRR). However, if the output signal, once amplified, must be single ended, then it may be better to have a floating capacitor with single-ended output in amplifiers and some multiplexers whereas in demodulators a floating capacitor with differential output yields a better CMRR.Peer Reviewe

Subsurface resistivity measurements using square waveforms

This work analyzes the effect of inductive and capacitive coupling between the injecting circuit and the detecting circuit in resistive field surveys. Theoretical and experimental results demonstrate that if a square waveform is injected into the soil, and synchronous sampling is used to sample at the flat zone of the detected voltage, then the effect of the interference is greatly reduced. Furthermore, square waveforms are easier to generate than sinusoidal waveforms, so they offer a new approach to subsurface resistivity measurements.Peer Reviewe

Trifoliata hybrids rootstocks for 'Lane Late' navel orange in Spain

Carrizo citrange [Citrus sinensis (L.) Osb. × Poncirus trifoliata (L.) Raf.] and Cleopatra mandarin (C. reshni Hort. ex Tan.) are the most important rootstocks used in Spain, but they are problematic and it is necessary to search for new rootstocks with better all-round performance. The performance of 'Lane Late' navel orange [Citrus sinensis (L.) Osb] on ten rootstocks was determined in the South of the province of Alicante (Spain). They are Carrizo citrange, Cleopatra mandarin and eight new hybrids obtained at the Instituto Valenciano de Investigaciones Agrarias in Valencia (Spain): 020324 [Troyer citrange (C. sinensis × P. trifoliata) × Cleopatra mandarin], Forner-Alcaide 418 (F&A 418) [Troyer citrange × common mandarin (C. deliciosa Ten.)], Forner-Alcaide 13 (F&A 13), 030118, 030127 and 030131 (Cleopatra mandarin × P. trifoliata) and 030212 and 030230 (Cleopatra mandarin × Troyer citrange). Soil is clay loam, with pH 8.5 and electric conductivity in the saturation extract at 25ºC of 5.79 mS cm-1. Yield was weighed during the first nine harvests, fruit quality was determined in the last three. Pre-harvest fruit-drop was controlled for the 4th until 9th harvests. The trees of 'Lane Late' navel budded on Cleopatra mandarin were the tallest (2.5 m) and F&A 418 (1.6 m) the shortest of all rootstocks tested. Trees on 030131 hybrid and Carrizo citrange rootstocks had the highest mean yield (81.2 and 80.3 kg per tree per year respectively), while trees on F&A 418 produced the lowest mean yield (22.3 kg per tree per year). Trees on 030131, 020324 and 030212 had the highest yield efficiency as total cumulative yield per cubic meter of canopy volume (62.1, 58.7 and 55.9 kg m-3 respectively) whereas trees on 030127, F&A 418 and Cleopatra mandarin had lower yield efficiencies (45.0, 44.4 and 38.6 kg m-3, respectively). Pre-harvest fruit-drop was lower in trees grafted on Cleopatra mandarin (24.62 %) and on 030212 (26.61 %), and was also low on F&A 418 (27.76 %), 020324 (28.14 %) and 030230 (29.18 %) rootstocks. Trees on Carrizo citrange and 030127 experienced important fruit-drop (40.24 % and 38.27 % respectively). Trees on F&A 418 had the highest fruit weight and fruit size whereas trees on 030118 induced the lowest ones. The ripeness index was the highest on F&A 13 (18.3) and lowest on F&A 418 (15.3), 030212 (15.3)

Mycotoxin exposure and human cancer risk : a systematic review of epidemiological studies

In recent years, there has been an increasing interest in investigating the carcinogenicity of mycotoxins in humans. This systematic review aims to provide an overview of data linking exposure to different mycotoxins with human cancer risk. Publications (2019 and earlier) of case–control or longitudinal cohort studies were identified in PubMed and EMBASE. These articles were then screened by independent reviewers and their quality was assessed according to the Newcastle–Ottawa scale. Animal, cross‐sectional, and molecular studies satisfied criteria for exclusion. In total, 14 articles were included: 13 case–control studies and 1 longitudinal cohort study. Included articles focused on associations of mycotoxin exposure with primary liver, breast, and cervical cancer. Overall, a positive association between the consumption of aflatoxin‐contaminated foods and primary liver cancer risk was verified. Two case–control studies in Africa investigated the relationship between zearalenone and its metabolites and breast cancer risk, though conflicting results were reported. Two case–control studies investigated the association between hepatocellular carcinoma and fumonisin B1 exposure, but no significant associations were observed. This systematic review incorporates several clear observations of dose‐dependent associations between aflatoxins and liver cancer risk, in keeping with IARC Monograph conclusions. Only few human epidemiological studies investigated the associations between mycotoxin exposures and cancer risk. To close this gap, more in‐depth research is needed to unravel evidence for other common mycotoxins, such as deoxynivalenol and ochratoxin A. The link between mycotoxin exposures and cancer risk has mainly been established in experimental studies, and needs to be confirmed in human epidemiological studies to support the evidence‐based public health strategies