11,929 research outputs found

    Lithium abundance evolution in open clusters: Hyades, NGC752, and M67

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    Mixing mechanisms bring the Li from the base of the convective zone to deeper and warmer layers where it is destroyed. These mechanisms are investigated by comparing observations of Li abundances in stellar atmospheres to models of stellar evolution. Observations in open cluster are especially suitable for this comparison, since their age and metallicity are homogeneous among their members and better determined than in field stars. In this work, we compare the evolution of Li abundances in three different clusters: the Hyades, NGC752, and M67. Our models are calculated with microscopic diffusion and transport of chemicals by meridional circulation, and calibrated on the Sun. These comparisons allow us to follow the evolution of Li abundance as a function of stellar mass in each cluster and as a function of the age by comparing this evolution in each cluster. We evaluate the efficiency of the mixing mechanisms used in the models, and we try to identify the lacking mechanisms to reproduce the observed evolution of Li abundance.Comment: 6 pages, 4 figures, conference publication of "New advances in stellar physics: from microscopic to macroscopic processes

    Os padrões e a resolução de problemas no 1º ciclo do ensino básico: potencialidades para o ensino-aprendizagem da matemática

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    Mestrado (PES II), Educação Pré-Escolar e Ensino do 1º Ciclo do Ensino Básico, 27 de Junho de 2014, Universidade dos Açores (Relatório de Estágio).[…]. Com a elaboração deste trabalho e refletindo sobre o percurso realizado, conclui-se que as tarefas implementadas, além de estimularem a identificação, construção e compreensão de padrões, proporcionaram aos alunos a oportunidade de comunicar em linguagem matemática e de generalizar padrões estudados, com claras vantagens para o desenvolvimento da capacidade de abstração. A exploração de padrões também contribuiu de forma pertinente para estimular o processo de resolução de problemas. Pudemos constatar que, nos primeiros anos de escolaridade, a descoberta de padrões e a resolução de problemas são grandes potenciadores da atividade matemática, ao nível das capacidades de visualização, imaginação, generalização e comunicação.ABSTRACT: […]. With the making of this work and looking back to the process that it took, we can conclude that the implemented tasks not only stimulated the identification, construction and comprehension of patterns, but also offered students the opportunity to communicate in a mathematical language and to generalize studied patterns, with clear advantages for the improvement of the capacity of abstraction. The development of patterns also pertinently contributed for the stimulation of the process of problem solving. We could observe that in the early school years the discovery of patterns and the resolution of problems foster the visualization, imagination, generalization and communication skills and in that sense, they contribute decisively to improve the quality oh mathematical activity in the classroom

    Fundamental education and decolonization of the mind

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    Education is a key topic in anticolonial and postcolonial scholarship and activism. There are several reasons for this: Firstly, education was a crucial element of imperialism, as colonial rule without an educational program, which enabled epistemic violence, is almost unthinkable. As Edward Said outlines in Orientalism (1978), it was as vital for colonial powers to teach the \u27other\u27 as to study the \u27other\u27 (see also Castro Varela & Dhawan, 2020). Only through colonial education, it was possible to produce a colonized population that relied on and trusted European knowledge and internalized specific Eurocentric norms of knowledge production. Colonial education was part and parcel of the civilizational mission, which is why it finds itself in an ambivalent position via-à-vis mass education. (DIPF/Orig.

    Activity schedule and foraging in Protopolybia sedula (Hymenoptera, Vespidae)

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    Protopolybia sedula is a social swarming wasp, widely spread throughout many countries in the Americas, including most of Brazil. Despite its distribution, studies of its behavioral ecology are scarce. This study aimed to describe its foraging activity and relation to climatic variables in the city of Juiz de Fora in southeastern Brazil. Three colonies were under observation between 07:00 and 18:00 during April 2012, January 2013, and March 2013. Every 30 minutes, the number of foragers leaving and returning to the colony was registered along with air temperature and relative humidity. Activity began around 07:30¸ increased between 10:30 and 14:30, and ended around 18:30. A mean of 52.7 exits and 54 returns were measured every 30 minutes. The daily mean values were 1,107 ± 510.6 exits and 1,135 ± 854.8 returns. Only one colony showed a significant correlation between forager exits and temperature (rs = 0.8055; P \u3c 0.0001) and between exits and relative humidity (rs = -0.7441; P = 0.0001). This paper shows that climatic variables are likely to have little control on the foraging rhythm of P. sedula when compared to other species, suggesting the interaction of other external and internal factors as stimuli of species foraging behavio

    Suplementos alimentares numa farmácia comunitária

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    Monografia realizada no âmbito da unidade de Estágio Curricular do Mestrado Integrado em Ciências Farmacêuticas, apresentada à Faculdade de Farmácia da Universidade de CoimbraA procura por um estilo de vida mais saudável implementou um crescimento na comercialização de produtos notificados como Suplementos Alimentares, aumentando assim a necessidade de uma maior fiscalização e uma maior colaboração entre as entidades competentes de modo a garantir a segurança alimentar para os consumidores. Considerados géneros alimentícios, os Suplementos Alimentares não necessitam de estudos de segurança e eficácia previamente à sua comercialização, estando a sua segurança responsabilizada pelo fabricante e a sua fiscalização pelas autoridades competentes. Os Suplementos Alimentares são considerados pela população seguros e inócuos e não necessitam de indicação médica, fatores que tornam o papel do Farmacêutico ainda mais relevante no aconselhamento prestado na farmácia comunitária. Previamente à dispensa do Suplemento Alimentar, o Farmacêutico deve tomar conhecimento da terapêutica habitual do utente, objetivando a identificação precoce de possíveis interações dos constituintes dos Suplementos Alimentares com a medicação habitual, garantindo assim a segurança do utente. A presente monografia teve como objetivos a análise da regulamentação dos Suplementos Alimentares em Portugal, a análise dos Suplementos Alimentares mais vendidos numa farmácia comunitária, as possíveis interações que poderão ocorrer aquando a sua toma com medicamentos e o papel do Farmacêutico.The seek for a healthier lifestyle enhanced the commercialization of notified products as Dietary Supplements, arising the need of a greater inspection and collaboration between the competent authorities in order to assure the food safety for the consumer. Considered as food, the Dietary Supplements don’t need safety and effectiveness studies before their commercialization, being the safety held by the manufacturer and the inspection by the competent authorities. The Dietary Supplements are considered safe and innocuous by the population and they don´t need medical indication, which make the role of the Pharmacist even more relevant in the provided counselling at the community pharmacy. Prior for the dispensing, the Pharmacist must be aware of the patient’s usual medication, aiming the early identification of possible interactions between the Dietary Supplements’ constituents and usual medication, assuring the patient’s safety. The present manuscript aimed at analyzing the Dietary Supplements’ regulatory system, the best sellers at the community pharmacy, the possible interactions that may occur during their administration with drugs and the role of the Pharmacist

    Survival Probability in Patients with Sickle Cell Anemia Using the Competitive Risk Statistical Model.

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    The clinical picture of patients with sickle cell anemia (SCA) is associated with several complications some of which could be fatal. The objective of this study is to analyze the causes of death and the effect of sex and age on survival of Brazilian patients with SCA. Data of patients with SCA who were seen and followed at HEMORIO for 15 years were retrospectively collected and analyzed. Statistical modeling was performed using survival analysis in the presence of competing risks estimating the covariate effects on a sub-distribution hazard function. Eight models were implemented, one for each cause of death. The cause-specific cumulative incidence function was also estimated. Males were most vulnerable for death from chronic organ damage (p = 0.0005) while females were most vulnerable for infection (p=0.03). Age was significantly associated (p ≤ 0.05) with death due to acute chest syndrome (ACS), infection, and death during crisis. The lower survival was related to death from infection, followed by death due to ACS. The independent variables age and sex were significantly associated with ACS, infection, chronic organ damage and death during crisis. These data could help Brazilian authorities strengthen public policies to protect this vulnerable population

    When not-for-profit try to influence firms

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    I study the influence of not-for-profit entities in companies, through shareholders proposals in the U.S. largest companies. This paper analyzes the not-for-profit entities involved, the issues addressed by the proposals and the financial characteristics of target companies, as well as market reactions and voting outcomes. Results indicate that not-for-profit entities tend to target companies with higher profitability and value more frequently than general investors. Furthermore, the voting outcome is influenced by insider ownership and types of proposals. Finally, market reactions change with profitability, leverage, ownership structure and types of proposals
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