Equações do 2.º grau do fim do século XIX ao início do século XXI: Uma análise de sete manuais escolares

Este artigo analisa o modo como as equações do 2.º grau são abordadas em sete manuais escola-res publicados entre o fim do século XIX e o início do século XXI, escolhidos entre os mais utilizados em cada período. Analisamos a forma como este assunto é apresentado em cada manual, incluindo a aborda-gem do tema, os exemplos e as tarefas propostas para o aluno resolver, bem como os contextos utilizados e a linguagem e grafismo. A análise realizada mostra que o assunto foi tendo um tratamento cada vez mais simplificado, tanto nos conteúdos como nas tarefas propostas e na linguagem, notando-se a influên-cia da Matemática moderna com a introdução de elementos da lógica e da teoria dos conjuntos. Ressalta, ainda, uma evolução muito interessante no uso dos termos “exercício” e “problema”. Numa primeira fase, os exercícios tendiam a ter grande complexidade e designavam-se por problemas os que tinham um enun-ciado em linguagem natural. Mais tarde, o termo “exercício” é substituído por “actividade”. No manual mais recente, o termo “exercício” desaparece e o termo “problema” passa a designar tarefas de tipo muito diversificado, incluindo tarefas extremamente simples.This paper analyses the way 2nd degree equation are studied in seven school mathematics text-books published between the end of the XIXth century and the beginning of the XXIst century, chosen among the most used in each period. We analyze the way this subject is presented in each textbook, in-cluding the way the theme is approached, the examples and the tasks proposed to the student, as well as the contexts used and the language and graphic style. The analysis undertaken shows that the topic had an approach increasingly simplified, in its content, in tasks proposed and in the language, and it can be noted an influence of modern mathematics with the introduction of elements of logic and set theory. It also stands a very interesting in the use of the terms “exercise” and “problem”. Ina first phase, the exercises had a great complexity. Those that were phrased in natural language were called problems. Later, the term “exercise” is substituted by “activity”. In the more recent textbook, the term “exercise” disappears and the term “problem” begins designating tasks of a much diversified nature, including very simple tasks

Specific micronutrient concentrations are associated with inflammatory cytokines in a rural population of Mexican women with a high prevalence of obesity

It has been recognised recently that obese individuals have lower concentrations of micronutrients and this may affect the concentrations of inflammatory cytokines. A cross-sectional study was carried out to evaluate the association of specific micronutrients' status with chronic inflammation caused by obesity in 280 women (36·1 (sd 7·5) years) from seven rural communities in Mexico. Measurements of weight, height and waist circumference were made on all women and body composition was determined by dual-energy X-ray absorptiometry. Concentrations of the cytokines IL-1, TNF-α, IL-6, IL-10 and IL-12, lipid profile, and the micronutrients Zn and vitamins A, C and E were determined in fasting blood samples. Ordered logistic regression models were used to determine associations between categorised cytokine levels and micronutrients. It was found that 80 % of women were overweight or obese, and had significantly higher concentrations of C-reactive protein than normal-weight women (P = 0·05). The risk of higher levels of TNF-α, IL-6, IL-10 and IL-12 was reduced significantly among women with higher Zn concentrations (OR 0·63, 95 % CI 0·42, 0·96, P = 0·03; OR 0·57, 95 % CI 0·39, 0·86, P = 0·025; OR 0·63, 95 % CI 0·41, 0·96, P = 0·04; OR 0·62, 95 % CI 0·41, 0·95, P = 0·03, respectively). Higher concentrations of vitamin A were slightly associated with reduced risks of higher levels of IL-1 and IL-12 (OR 0·97, 95 % CI 0·95, 0·99, P = 0·03; OR 0·97, 95 % CI 0·94, 0·99, P = 0·03, respectively); when adjusting for BMI, this association was lost. No associations were found between vitamin C or vitamin E:lipids concentrations and inflammatory cytokines. In conclusion, higher Zn concentrations are associated with reduced risks of higher concentration of inflammation markers in a population of women with a high prevalence of obesity

Effects of 1-year intervention with a mediterranean diet on plasma fatty acid composition and metabolic syndrome in a population at high cardiovascular risk

Background & Aims: Metabolic syndrome (MetS) has become an important public concern due to its increasing prevalence. An altered fatty acid composition has been associated with MetS, but the Mediterranean diet has been shown to have a protective effect. The aim of the present study was to analyze the influence of a Mediterranean dietary pattern, as assessed by the biomarkers of food supplied, on the plasma fatty acid composition and its relation with MetS after 1 year of intervention. Methods: A total of 424 subjects were randomly selected from the PREDIMED randomized dietary trial after completing a 1- year intervention program. Participants aged 55 to 80 years and at high risk of cardiovascular disease were randomly assigned to three dietary interventions: Mediterranean diet supplemented with virgin olive oil or nuts, or a low-fat diet. Results: After 1 year of intervention participants in the virgin olive oil group showed significantly increased plasma concentrations of palmitic and oleic acids, but reduced proportions of margaric, stearic, and linoleic acids. In turn, subjects in the nut group showed significantly increased levels of palmitic, linoleic, and a-linolenic acids, but reduced proportions of myristic, margaric, palmitoleic, and dihommo-c-linoleic acids. Increases in the biomarkers of foods supplied to the Mediterranean diet groups, i.e., oleic and a-linolenic acids, were beneficially associated with the incidence, reversion and prevalence of MetS. No weight changes were observed among participants. Conclusions: The nut and olive oil diets induced a fatty acid composition that has been shown to be beneficial in the face of MetS. Therefore, a Mediterranean diet rich in fats of vegetable origin may be a useful tool for the management of MetS without the need for concerns over weight gain due to its high fat content

Central blood pressure and pulse wave velocity: relationship to target organ damage and cardiovascular morbidity-mortality in diabetic patients or metabolic syndrome. An observational prospective study. LOD-DIABETES study protocol

<p>Abstract</p> <p>Background</p> <p>Diabetic patients show an increased prevalence of non-dipping arterial pressure pattern, target organ damage and elevated arterial stiffness. These alterations are associated with increased cardiovascular risk.</p> <p>The objectives of this study are the following: to evaluate the prognostic value of central arterial pressure and pulse wave velocity in relation to the incidence and outcome of target organ damage and the appearance of cardiovascular episodes (cardiovascular mortality, myocardial infarction, chest pain and stroke) in patients with type 2 diabetes mellitus or metabolic syndrome.</p> <p>Methods/Design</p> <p><b>Design</b>: This is an observational prospective study with 5 years duration, of which the first year corresponds to patient inclusion and initial evaluation, and the remaining four years to follow-up.</p> <p><b>Setting</b>: The study will be carried out in the urban primary care setting.</p> <p><b>Study population</b>: Consecutive sampling will be used to include patients diagnosed with type 2 diabetes between 20-80 years of age. A total of 110 patients meeting all the inclusion criteria and none of the exclusion criteria will be included.</p> <p><b>Measurements</b>: Patient age and sex, family and personal history of cardiovascular disease, and cardiovascular risk factors. Height, weight, heart rate and abdominal circumference. Laboratory tests: hemoglobin, lipid profile, creatinine, microalbuminuria, glomerular filtration rate, blood glucose, glycosylated hemoglobin, blood insulin, fibrinogen and high sensitivity C-reactive protein. Clinical and 24-hour ambulatory (home) blood pressure monitoring and self-measured blood pressure. Common carotid artery ultrasound for the determination of mean carotid intima-media thickness. Electrocardiogram for assessing left ventricular hypertrophy. Ankle-brachial index. Retinal vascular study based on funduscopy with non-mydriatic retinography and evaluation of pulse wave morphology and pulse wave velocity using the SphygmoCor system. The medication used for diabetes, arterial hypertension and hyperlipidemia will be registered, together with antiplatelet drugs.</p> <p>Discussion</p> <p>The results of this study will help to know and quantify the prognostic value of central arterial pressure and pulse wave velocity in relation to the evolution of the subclinical target organ damage markers and the possible incidence of cardiovascular events in patients with type 2 diabetes mellitus.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov Identifier: NCT01065155</p

Regulation of the Na+/K+-ATPase Ena1 Expression by Calcineurin/Crz1 under High pH Stress: A Quantitative Study

[EN] Regulated expression of the Ena1 Na+-ATPase is a crucial event for adaptation to high salt and/or alkaline pH stress in the budding yeast Saccharomyces cerevisiae. ENA1 expression is under the control of diverse signaling pathways, including that mediated by the calcium-regulatable protein phosphatase calcineurin and its downstream transcription factor Crz1. We present here a quantitative study of the expression of Ena1 in response to alkalinization of the environment and we analyze the contribution of Crz1 to this response. Experimental data and mathematical models substantiate the existence of two stress-responsive Crz1-binding sites in the ENA1 promoter and estimate that the contribution of Crz1 to the early response of the ENA1 promoter is about 60%. The models suggest the existence of a second input with similar kinetics, which would be likely mediated by high pH-induced activation of the Snf1 kinase.This work was supported by grants BFU2011-30197-C3-01, BFU2014-54591-C2-1-P and EUI2009-04147 (SysMo2) to JA. (Ministry of Industry and Competitivity, Spain, and Fondo Europeo de Desarrollo Regional [FEDER]). JA is the recipient of an Ajut 2014SGR-4 award (Generalitat de Catalunya). DC was recipient of a predoctoral fellowship from the Spanish Ministry of Education. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Petrezsélyová, S.; López-Malo, M.; Canadell, D.; Roque, A.; Serra-Cardona, A.; Marques Romero, MC.; Vilaprinyó, E.... (2016). Regulation of the Na+/K+-ATPase Ena1 Expression by Calcineurin/Crz1 under High pH Stress: A Quantitative Study. PLoS ONE. 11(6):e0158424-e0158424. https://doi.org/10.1371/journal.pone.0158424Se0158424e015842411

Dietary a-Linolenic acid, Marine x-3 fatty acids, and mortality in a population with high fish consumption: findings from the PREevención con DIeta MEDiterránea (PREDIMED) study

Epidemiological evidence suggests a cardioprotective role of α‐linolenic acid (ALA), a plant‐derived ω‐3 fatty acid. It is unclear whether ALA is beneficial in a background of high marine x-3 fatty acids (long-chain n-3 polyunsaturated fatty acids) intake. In persons at high cardiovascular risk from Spain, a country in which fish consumption is customarily high, we investigated whether meeting the International Society for the Study of Fatty Acids and Lipids recommendation for dietary ALA (0.7% of total energy) at baseline was related to all-cause and cardiovascular disease mortality. We also examined the effect of meeting the society’s recommendation for long-chain n-3 polyunsaturated fatty acids (≥500 mg/day). Methods and Results-—We longitudinally evaluated 7202 participants in the PREvenci on con DIeta MEDiterr anea (PREDIMED) trial. Multivariable-adjusted Cox regressionmodels were fitted to estimate hazard ratios. ALA intake correlated towalnut consumption (r=0.94). During a 5.9-y follow-up, 431 deaths occurred (104 cardiovascular disease, 55 coronary heart disease, 32 sudden cardiac death, 25 stroke). The hazard ratios formeeting ALArecommendation (n=1615, 22.4%) were 0.72 (95% CI 0.56–0.92) for all-causemortality and 0.95 (95% CI 0.58–1.57) for fatal cardiovascular disease. The hazard ratios formeeting the recommendation for long-chain n-3 polyunsaturated fatty acids (n=5452, 75.7%) were 0.84 (95% CI 0.67–1.05) for all-causemortality, 0.61 (95% CI 0.39–0.96) for fatal cardiovascular disease, 0.54 (95% CI 0.29–0.99) for fatal coronary heart disease, and 0.49 (95% CI 0.22–1.01) for sudden cardiac death. The highest reduction in all-cause mortality occurred in participants meeting both recommendations (hazard ratio 0.63 [95% CI 0.45–0.87]). Conclusions-—In participants without prior cardiovascular disease and high fish consumption, dietary ALA, supplied mainly by walnuts and olive oil, relates inversely to all-cause mortality, whereas protection from cardiac mortality is limited to fish-derived long-chain n-3 polyunsaturated fatty acids

Polyphenol intake and mortality risk: a re-analysis of the PREDIMED trial

Background: Polyphenols may lower the risk of cardiovascular disease (CVD) and other chronic diseases due to their antioxidant and anti-inflammatory properties, as well as their beneficial effects on blood pressure, lipids and insulin resistance. However, no previous epidemiological studies have evaluated the relationship between the intake of total polyphenols intake and polyphenol subclasses with overall mortality. Our aim was to evaluate whether polyphenol intake is associated with all-cause mortality in subjects at high cardiovascular risk. Methods: We used data from the PREDIMED study, a 7,447-participant, parallel-group, randomized, multicenter, controlled five-year feeding trial aimed at assessing the effects of the Mediterranean Diet in primary prevention of cardiovascular disease. Polyphenol intake was calculated by matching food consumption data from repeated food frequency questionnaires (FFQ) with the Phenol-Explorer database on the polyphenol content of each reported food. Hazard ratios (HR) and 95% confidence intervals (CI) between polyphenol intake and mortality were estimated using time-dependent Cox proportional hazard models. Results: Over an average of 4.8 years of follow-up, we observed 327 deaths. After multivariate adjustment, we found a 37% relative reduction in all-cause mortality comparing the highest versus the lowest quintiles of total polyphenol intake (hazard ratio (HR) = 0.63; 95% CI 0.41 to 0.97; P for trend = 0.12). Among the polyphenol subclasses, stilbenes and lignans were significantly associated with reduced all-cause mortality (HR =0.48; 95% CI 0.25 to 0.91; P for trend = 0.04 and HR = 0.60; 95% CI 0.37 to 0.97; P for trend = 0.03, respectively), with no significant associations apparent in the rest (flavonoids or phenolic acids). Conclusions: Among high-risk subjects, those who reported a high polyphenol intake, especially of stilbenes and lignans, showed a reduced risk of overall mortality compared to those with lower intakes. These results may be useful to determine optimal polyphenol intake or specific food sources of polyphenols that may reduce the risk of all-cause mortality. Clinical trial registration: ISRCTN35739639

A comunicação na aula de Matemática : um estudo com dois professores do 3.º ciclo do ensino básico

Tese de mestrado, Educação (Didáctica da Matemática), Universidade de Lisboa, Faculdade de Ciências, 2008Este estudo procura conhecer a comunicação na aula de Matemática do 3 ° ciclo, analisando os problemas que isso coloca à prática profissional do professor. Assim, pretende responder às seguintes questões: Que importância atribuem os professores à comunicação matemática na aprendizagem dos alunos? Como se desenvolvem as suas práticas de comunicação na sala de aula? Que modos de comunicação e que formas de promover a comunicação estão subjacentes à actividade matemática na sala de aula? O enquadramento teórico discute a importância da comunicação e as funções da linguagem na aula de Matemática e analisa as perspectivas teóricas sobre a comunicação em educação matemática, incluindo as formas e modos de comunicação. A metodologia de investigação segue o paradigma qualitativo de cunho interpretativo apoiado em dois estudos de caso. A recolha de dados foi realizada durante o ano lectivo de 2005/06 através de observação de aulas, entrevistas e análise documental. Os resultados deste estudo mostram o gosto dos dois professores em reflectir sobre a prática, nomeadamente sobre a comunicação na sala de aula. Ambos relacionam o ensino da Matemática com a transmissão de conteúdos matemáticos e o desenvolvimento da capacidade dos alunos para reflectirem sobre os conceitos. Nas suas práticas de comunicação, os professores incentivam a comunicação oral e escrita de modo a compreenderem o raciocínio dos alunos. As principais formas de comunicação que ambos os professores recorrem durante as suas práticas são o questionamento para o esclarecimento de dúvidas e a exposição para explicação dos conceitos. Relativamente aos modos de comunicação, destaca-se em ambos o modo contributivo.The goal of this study is to know how it is communication in the mathematics classroom of the cycle of basic education, by analysing the problems that this brings to the professional practice of the teacher. Therefore, it aims to answer the following questions: What importance do teachers place on mathematics communication for students' learning? How do they develop their classroom communication practices? What kind of communication and what ways to promote communication underline the mathematics classroom activity? The theoretical framework discusses the importance of communication and the functions of language in the mathematics class and analyses the theoretical perspectives on communication in mathematics learning, including communication types and modes. The investigation methodology follows a qualitative paradigm of an interpretative nature and is based on two case studies. The data was collected during the school year 2005/06 and the methods used were lesson observation, interviews and documental analysis. The results of this study show that both teachers enjoy to reflect on their practice, notably regarding classroom communication. Both relate the teaching of mathematics to the transmission of mathematical contents and to the development of students' capacities of refection on these concepts. In terms of communication, the teachers stimulated oral and written communication in order to understand students' reasoning. The main types of communication both teachers use in their practices were questioning to answer doubts and exposing to explain concepts. Regarding the types of communication, both teachers mainly use the contributive mode

Programación por competencias en educación infantil : del proyecto educativo al desarrollo integral del alumno

Resumen basado en el de la publicaciónSe aborda de manera teórico-práctica los principios generales de la programación por competencias en educación infantil. Se expone el desarrollo de las competencias básicas en la LOE, sus finalidades y funciones, cómo realizar una programación en educación infantil y propuestas prácticas de programación según competencias. Incluye ejercicios de autoevaluación.GaliciaBiblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín 5 -3 Planta; 28014 Madrid; Tel. +34917748000; [email protected]