A presente dissertação é relativa a uma investigação sobre as potencialidades e limitações do trabalho de um grupo colaborativo durante a formação inicial de professores que ensinam frações. Participaram da pesquisa alunos de um curso de Pedagogia. O objetivo principal da pesquisa foi identificar as concepções de frações que os estudantes apresentam e analisar de que modo a participação nas atividades de um grupo colaborativo podem contribuir para o processo de ressignificação de tais concepções. Para tanto, constituiu-se um grupo de oito alunas de um curso de Pedagogia, que interagiram durante um total de oito encontros, nos quais foram produzidos os dados para a análise. Como referencial teórico nos aproximamos da teoria sócio-histórica de Vygostky, da educação matemática crítica de Skovsmose e dos estudos sobre grupos colaborativos e das comunidades de prática, dentre outros que tomam por objeto a formação de professores que ensinam matemática, em especial nos cursos de Pedagogia. A abordagem metodológica adotada foi a qualitativa com a utilização de diferentes tipos de registros, permitindo a triangulação dos dados. Identificamos alguns limitadores durante o percurso: o período curto de realização do trabalho, a postura dos participantes internalizada e apropriada através do ambiente acadêmico que reproduz crenças e discursos sem uma adequada construção conceitual e, principalmente, significativas dificuldades com relação ao conteúdo matemático de frações. Em contrapartida, algumas características ou dimensões de um grupo colaborativo foram evidenciadas. Os participantes demonstraram diferentes identidades de participação, compartilharam um objetivo comum, um empreendimento mútuo e as tarefas foram compartilhadas. A pesquisadora, como sendo também uma integrante do grupo, foi provocada a desenvolver as diferentes dimensões de sua participação. Nesse sentido, a pesquisa mostrou ser viável o trabalho com grupos colaborativos na formação inicial considerando o contexto, particularidades dos participantes da pesquisa e as atividades desenvolvidas. / This thesis reports a research about the potentialities and restrictions of collaborative group work during initial training of teachers who teach fractions. Teaching academics took part in this research. The main objective was to identify the notion of fractions held by the students and to analyze the way in which participation in the activities of a collaborative group may contribute to the process of re-establishing the meaning in those conceptions. In order to do so, a total of eight students of the teaching course interacted in eight meetings through which data was produced for the analysis. As a theoretical basis we used Vykotsky’s Socio-historical Approach, Critical Mathematics Education by Skovsmose and studies about collaborative work, communities of practice, among others whose object is vocational training of Math teachers, especially in teaching courses. The methodological approach chosen was qualitative and interpretative with the use of different types of register, allowing triangulation of data. Some limitations were identified in the process: the short duration of the project, participants’ attitudes internalized and borrowed from the academic environment, which reproduces beliefs and discourses without an appropriate conceptual construction, and, mainly, important difficulties related to the mathematical subject: fractions. On the other hand, some characteristics or dimensions of a collaborative group were evidenced. The participants demonstrated different identities of participation, shared a common objective, a mutual undertaking and the tasks were shared. The researcher, as part of the group, was provoked to develop different dimensions of participation. The group knew how to determine priorities, drawing its paths and building its history of participation. This way, the research showed that working with collaborative groups in teachers’ education is practicable, taking into account the context and particularities of the participants and the activities developed.

O estudo da digestibilidade e do aproveitamento biológico do feijão (Phaseolus vulgaris, L. ),variedade Carioca e de suas principais frações protéicas foi realizado em ensaios biológicos com ratos, após tratamento térmico adequado (cocção). À metodologia convencional, baseada no \"Ganho de Peso\" e na razão entre o N ingerido e excretado, seguiu-se uma técnica utilizando feijões e suas frações protéicas previamente marcadas com 15N e 35S. A ingestão das rações causou respostas diferentes nos animais, específicos para cada fonte protéica. Os animais alimentados com o feijão integral tiveram reduzido aproveitamento biológico e excretaram 34% do nitrogênio ingerido, sendo este valor 3-4 vezes superior ao causado pela ingestão da ração controle de caseína. As frações, albumínicas e glutelínicas, apresentaram valores de \"NPR\" e \"Ganhos de Peso\" superiores, apesar de sua relativa baixa digestibilidade (70-80%). A globulina G1, altamente digerível (92%) teve uma utilização biológica muito reduzida, não permitindo o crescimento dos animais. O ensaio biológico do feijão e de suas proteínas, marcados isotopicamente, permitiu diferenciar a origem do nitrogênio e do enxofre fecal, se endógena ou exógena. A concentração de 15N em excesso, determinado nas fazes 12 horas após o início da ingestão das rações marcadas, consideramos ser de origem exógena, sendo esses valores interpretados comparativamente. A ingestão de feijões cozidos causou nos animais uma excreção de nitrogênio proveniente do próprio feijão, 10 vezes superior à elevada perda de nitrogênio endógeno, totalizando o equivalente a 34% do nitrogênio ingerido. Ratos alimentados com a globulina G1 excretaram nas primeiras 12 horas apenas quantidades muito reduzidas de 15N, e mesmo na fase de equilíbrio (4º - 6º dia de ingestão da reação marcada ) quando o 15N excretado corresponde ao exógeno + endógeno já marcado, a perda de N total não ultrapassou 10% do ingerido. A ingestão da fração albumínica, por sua vez, causou uma eliminação de 20% do N total ingerido, com participação tanto do N exógeno como endógeno. A interpretação dos resultados baseados na eliminação do enxofre e de seu radioisótopo 35S, mostrou um perfil de excreção semelhante ao observado para o 15N, embora em níveis levemente superiores. / Studies with growing rats were carried out to determine the digestibility, and nutritive value of beans (Phaseolus vulgaris, L.) Carioca variety, and their major protein fractions, after proper heat treatment in order to inactivate the antiphysiological factors. The conventional method based on weight gain and the relation between the ingested and excreted nitrogen was followed by a balance technique, employing either whole beans or their protein fractions, previously labeled with 15N and 35S. The ingestion of the diets showed different nutritive responses, which were specific for each of the diets. Low biological value and digestibility were observed by rats fed on whole bean-containing diets, and as a consequence an excretion of 34% the ingested nitrogen was noted. This value was 3-4 times higher than the one excreted by the casein-control animals. Higher vakues of \"weight gain\" and NPR were obtained with the albumin and glutelin based diets, although their digestibilities were relatively low (70 - 80%). The globulin G1 was highly digestible (92%) nevertheless it appeared to have very low nutritional values and did not allow the growth of rats. The biological assay with isotopically labeled beans and proteins, allowed to differenciate the origin of fecal nitrogen and sulfur, as exogenous or endogenous. The concentration of 15 N in excess, which appeared in the feces 12 hours after the first ingestion of the labeled diets, was considered to be of exogenous origin; these values can be interpreted comparatively. The ingestion of the cooked whole beans promoted an excretion of exogenous nitrogen, 10 times higher than that excreted by the rats on the globulin G1 diet, which with the high excretion of endogenous nitrogen, totalized 34% of the ingested one. Rats fed on the globulin G1 excreted, in the first 12 hours, only small amounts of 15N, even in the steady - state (4º - 6ºth day on feeding the labeled diet), when the excreted 15N corresponded to both, exogenous and labeled endogenous excretion reached, the maximum loss (about 10% of the ingested total nitrogen). The feeding of albumin based diets stimulated an excretion of 20% of the ingested nitrogen, due to exogenous and endogenous origin. The interpretation of the results based on the balance of total sulfur and their radioactive isotope (35S) showed an excretion pattern, similar to that of the 15N, although in absolute values (of excretion) it was a little higher than that representing the nitrogen loss.

Egyptian fractions are what we know as unit fractions that are of the form 1/n - with the exception, by the Egyptians, of 2/3. Egyptian fractions have actually played an important part in mathematics history with its primary roots in number theory. This paper will trace the history of Egyptian fractions by starting at the time of the Egyptians, working our way to Fibonacci, a geologist named Farey, continued fractions, Diophantine equations, and unsolved problems in number theory.

Orientador: Ernandes Rocha Oliveira / Resumo: Este trabalho reflete os resultados de uma pesquisa cuja preocupação é compreender as possibilidades e contribuições que um convite a um processo de autoformação por parte de professores que lecionam matemática pode trazer aos próprios professores e na melhoria de suas práticas e assim buscar ações com o propósito de colaborar com a área de formação de professores. Por meio de discussões amparadas em textos e de uma proposta de ensino utilizando um material concreto reunimos alguns professores dos primeiros anos do ensino fundamental, formados em Pedagogia, de uma escola pública do estado de São Paulo em conversas com a própria prática, pautadas na pedagogia crítica, com o propósito de criar um ambiente propício para o desenvolvimento profissional. O convite foi feito visando enriquecer o repertório matemático dos professores dos anos iniciais que ensinam matemática, mais precisamente em relação ao conteúdo de frações para que estes se sintam mais confortáveis para desenvolverem seu trabalho diante do seu alunado. Também procuramos reconhecer algumas possíveis lacunas na formação acadêmica inicial desses professores. Tendo como questão norteadora as possibilidades e contribuições que a utilização de um material concreto pode trazer a um grupo de professores, fazendo-os pensar, refletir, sobre o ensino de frações e se aprofundar neste estudo, e como a organização de um grupo de estudo com professores em uma escola pode influenciar em suas práticas e assim permitir uma autoform... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work reflects the results of a research whose concern is to understand the possibilities and contributions that an invitation to a process of self-formation by teachers who teach mathematics can bring to the teachers themselves and in the improvement of their practices and thus seek actions with the purpose to collaborate with teacher education. Through discussions based on texts and a proposal of teaching using a concrete material we gathered some teachers of the first years of elementary education, graduated in Pedagogy, from a public school in the state of São Paulo in conversations with the practice itself, based on critical pedagogy , with the purpose of creating an environment conducive to professional development. The invitation was made to enrich the mathematical repertoire of the teachers of the early years who teach mathematics, more precisely in relation to fractions so that they feel more apt and comfortable to develop their work before their student. We also sought to recognize some possible gaps in the initial academic formation of these teachers. Having as a guiding question the possibilities and contributions that the use of a concrete material can bring to a group of teachers, making them think, reflect on the teaching of fractions and deepen in this study, and how the organization of a study group with teachers in a school can influence their practices and thus allow a collective self-formation of teachers. As a result, in this group there was an expans... (Complete abstract click electronic access below) / Mestre

Orientador: Mara Cristina Pessôa da Cruz / Coorientador: Edson Luiz Mendes Coutinho / Banca: Felipe Batistella Filho / Banca: Flávia Fernanda Simili / Banca: José carlos Barbosa / Banca: Itamar Andrioli / Resumo: A intensificação da produção dos animais em sistemas confinados gera uma alta produção de esterco bovino que pode contribuir para o fornecimento de nutrientes. Além de proporcionar melhorias em atributos químicos e físicos do solo. Diante deste contexto trabalhou-se com a hipótese de que o esterco bovino pode substituir total ou parcialmente o fertilizante nitrogenado industrial na adubação do capim-tifton 85. Assim, o objetivo com o presente trabalho foi avaliar o efeito da combinação nitrogênio x esterco da produção de capim-tifton 85 e em atributos químicos e físicos do solo. O experimento foi instalado durante os anos agrícolas 2013-2014 e 2014-2015. Os tratamentos consistiram de cinco doses de nitrogênio (N): 0, 50, 100, 200 e 300 kg ha-1, e cinco doses de esterco (E): 0, 10, 20, 40 e 60 Mg ha-1 combinadas em esquema fatorial. As doses de 300 kg ha-1 de N e 40 Mg ha-1 de E proporcionaram a maior produção de massa seca (10.469 kg ha-1) e altura (75,10 cm) em 2013-14. A associação das maiores doses de esterco e nitrogênio resultaram em melhor desempenho da forrageira em relação a produção de massa seca total (13.305 kg ha-1). Houve aumento de 71 e 88% de acúmulo de nitrogênio no capim-tifton 85 no ano agrícola 2013-14 e, aumento de 126 e 163 em 2014-15, com o uso de esterco e de N-ureia, respectivamente. A recuperação aparente de N com o uso de esterco foi maior no segundo ano de avaliação. Com o uso de N-ureia não houve variação nos teores de carbono orgânico do solo e na... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Intensified production of animals in confined systems generates a high production of cattle manure that can contribute to the nutrient supply. In addition to providing improvements in soil chemical and physical attributes. In this context, we worked with the hypothesis that bovine manure can totally or partially replace industrial nitrogen fertilizer in fertilization of tifton grass 85. Thus, the objective with the present work was to evaluate the effect of the nitrogen and manure combination of tifton 85 grass production and on soil chemical and physical attributes. The experiment was installed during the agricultural years 2013-2014 and 2014-2015. The treatments consisted of five doses of nitrogen (N): 0, 50, 100, 200 and 300 kg ha-1, and five manure doses (E): 0, 10, 20, 40 and 60 Mg ha-1 combined in factorial scheme. The doses of 300 kg ha-1 of N and 40 Mg ha-1 of E provided the highest dry mass production (10,469 kg ha-1) and height (75,10 cm) in 2013-14. The association of the highest doses of manure and nitrogen resulted in better forage performance in relation to the production of total dry mass (13,305 kg ha-1). There was an increase of 71 and 88% of nitrogen accumulation in Tifton 85 grass in the agricultural year 2013-14 and, increased 126 and 163 in 2014-15, respectively. The apparent recovery of N with use of manure was greater in the second year of evaluation. With the use of N-urea, there was no change in soil organic carbon and forms of carbon associated with minerals and particulate. The use of 60 Mg ha-1 of manure for two consecutive years increased the stability (94.96%) and the weighted average diameter of the aggregates (4.86 mm) and decreased soil resistance to penetration (0.99 MPa) due to the 35% increase in soil carbon content. / Doutor

This work deals with the study of organic matter in the South Moravian lignite using the available physico-chemical methods and the results obtained are eventually considered for non-energy applications of lignite. Lignite organic matter was studied by degradation methods, which included CuO oxidation, thermochemolysis with TMAH and DFRC method. Special attention was paid to the lignite oxidation with hydrogen peroxide, which was carried out under different reaction conditions (time and temperature). Thermal degradation was performed in an inert atmosphere in order to observation of chemical change of lignite (including lignite after extraction with chloroform, demineralised lignite, remineralised lignete) during pyrolysis by means of various methods, especially TG-FTIR for analysis of gaseous products and FTIR for analysis the residual lignite after pyrolysis. Further, water-soluble fractions from lignite were characterized, particularly in terms of the content of organic substances.

No description available.

No description available.

The study investigated the effect of a videodisc-based, teacher-controlled, direct instruction-based program in fractions content, on self-concept. Self-concept was operationally defined as scores on a slightly modified version of Marsh's Self-Description Questionnaire (Marsh, 1988). A quasi-experimental, nonequivalent control group design was used to compare the self-report self-concept of two groups of upper elementary students (N = 337). The treatment group (n = 171) received instruction in fractions via the teacher-directed, videodisc-based, Mastering Fractions program (Systems Impact, 1986a). The control group (n = 166) received their normal grade four or grade five mathematics program, but did not include common fractions. Differences in achievement scores provided support for previous findings regarding the Mastering Fractions program. The treatment group covariance-adjusted mean on a criterion-referenced test was higher than that of the control (5.9 standard deviations). Differences in achievement test scores among the treatment classes varied directly with the levels of program implementation across classes. The data were examined using both the student and the class as the unit of analysis. Using the student as the unit of analysis, the treatment group mathematics self-concept covariance-adjusted mean was 0.22 standard deviations above that of the control group. An analysis of raw gain scores yielded a standardized mean difference effect size between the treatment and control group scores of +.12. A statistically significant but small main effect was also noted across student pretest achievement levels. The posttest difference between low-achiever means treatment versus control students is slightly larger than the difference between high-achiever means. No statistically significant interaction was noted between student achievement level at pretest and treatment condition. The class was also used as the unit of analysis. In this case the mean difference effect sizes between experimental groups were +0.86 (ANCOVA) and +0.34 (raw gain scores). Differences were small to moderate, but consistent with the study hypotheses. Recommendations are presented regarding future research and the use of direct instruction in school settings. (197 pages)

Abstact This thesis investigate the impact of smoking on the development of cancer. The main goal of this thesis is to determine the effect of smoking on the development of cancer in Czechia in the years 1978, 1988, 1998, 2008 and 2018 with a focus on differences in time, gender and age groups. The secondary goal of the thesis is to determine the distribution of smoking prevalence by gender, age groups and level of education, as well as the dependence of smoking prevalence on the level of education, social differences in the influence of smoking on cancer. The analytical part of the work uses the method of age-standardized incidence rate, population attributable fraction and the method of binary logistic regression. Data from the Institute of Health Information and Statistics of the Czech Republic, the Czech Statistical Office and Eurostat were used for the analysis. It has been shown that the prevalence of smoking depends on the level of education, where the probability of smoking is higher in people with a lower level of education than in people with a high level of education. In Czechia, between 1978 and 2018, the impact of smoking on the development of cancer decreased. While the impact of smoking on the development of cancer decreased in men, it was possible to observe an increase of the impact of...