675 research outputs found

    Soil quality and agricultural sustainability in the Brazilian Cerrado.

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    The "Cerrado Region" - the acid savannas of Brazil, as many as thirty years ago, were considered as ecosystem unsuitable for agriculture crop production because environmental limitations. However, a burst in agricultural development has taken place in the area during last decades as a result of new technology mainly involving plant breeding and soil management. In spite of the great contribution made by the "Cerrado" region to the Brazilian agricultural production, over the past few years concerns have been raised about the issue of the high costs of this agriculture production and about the issue of soil quality degradation, and how it could affect the sustainability of the agriculture in the "Cerrado" ecosystem. The concept of sustainable agriculture is well recognized research, development, and productive segments of today's agriculture, however, the notion of how to measure and monitor sustainability of farming systems is much les understood. This paper proposes a system of measuring and monitoring the sustainability of farming systems using soil quality indicators in the acid savannas of Brazil. The methodology utilized and agroecological framework to examine the relations among natural resources and agriculture, selectiong one agroecological zone inserted in the cerrado ecosystem. This selected zone was subdivided into regions superimposing Census data, because policy and socioeconomic differences among regions have a considerable influence on land-use systems and options. Target areas were selected and participatory rural appraisal procedure was used to supplement voids in data, identify and characterize predominant farming systems, and to capture farmer knowledge. Using this farmer knowledge, research results already available and local observations, the mainly factors affecting soil quality were identified. Assuming that a management system is sustainable only when soil quality is maintained of improved, physical, chemical and biological properties, processes and characteristics were closen as indicators to make qualitative and quantitative assessment of the changes in soil quality. Based upon these evaluations, a general procedure or framework for sustainability assessment was developed. Using the procedure, it is possible to identify whether current management interventions are contributing towards or away from sustainable farming management, and to develop strategies to improve sustainability of those systems

    Students’ engagement in school and creativity professed by students and assigned to teachers: A literature review

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    Este E-Book reúne um conjunto de investigações apresentadas no “I Congresso Internacional Envolvimento dos Alunos na Escola: Perspetivas da Psicologia e Educação” (ICIEAE), organizado no âmbito do “Projeto PTDC/CPE-CED/114362/2009 - Envolvimento dos Alunos na Escola: Diferenciação e Promoção” (EAE-DP), financiado pela Fundação para a Ciência e a Tecnologia (FCT).This article reviews the literature on the relation between creativity (as a personal and a contextual variable) and students’ engagement in school. In order to describe the state of art of student’s engagement in school and creativity, we prepared a narrative review. In general, literature shows a prevalence of studies relating creativity and giftedness; students with above average skills are, as a rule, characterized, among other criteria, by the presence of creativity and the existence of high motivation for learning. As a personal variable, creativity relates positively with self-concept and academic performance, appearing as an aspect worth encouraging in the student. Moreover, studies on the impact of the learning environments on student’s performance also suggest a positive relationship between the classroom climate and academic outcomes. Although studies on the relationship between creativity and the students’ behavior appear inconsistent, the teacher’s creativity, applied to the teaching-learning process, and perceived by the student, appears related to school satisfaction and academic performance. This brief review highlights the value of including creativity in teaching practices, drawing attention to the lack of studies and the need to develop research, both relational and quasi-experimental, on the relationship between creativity and students’ engagement in school and its effects

    Molecular model of TriBP1, a protein involved in nuclear import.

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    Further structural analysis will be performed in order to understand the biological properties and roles of TriBP1 and TriBP2.X-meeting 2007

    Portuguese Adaptation of Students Engagement in Schools International Scale (SESIS)

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    The importance of student’s engagement has been recently pointed out in research. However, there has been a lack of engagement assessment instrument, pertaining psychometric qualities. Objective: This paper presents the Portuguese adaptation of the “Student’s Engagement in School International Scale” (SESIS), drawn up from a12 countries international study (Lam et al., 2012; Lam et al., in press). Method: Psychometric properties of this scale were examined with data from 685 students from different grades (6th, 7th, 9th and 10th), from both sexes, and different regions of the country. Results: Factorial analysis of the results, with varimax rotation, lead to three different factors which explain 50.88% of the variance. The scale integrates the original 33 items, and cognitive, affective and behavioural dimensions. For the external validity study, the relationship between student’s engagement in school results and other school variables — academic performance, self-concept — was considered, and significant relations were observed, as expected. Conclusion: The data presented highlights the qualities of SESIS, as well as its usefulness for research purposes. Suggestion: It is suggested the investigation of the extension of SESIS’s three-dimensionality, in future studiesKeywords: Innovation, technology, research projects, etc. [Arial 10-point, justified alignment]

    Systematic Review and Meta-analysis of Long-term survival After Elective Infrarenal Abdominal Aortic Aneurysm Repair 1969-2011: 5 Year Survival Remains Poor Despite Advances in Medical Care and Treatment Strategies.

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    BACKGROUND: Improved critical care, pre-operative optimization, and the advent of endovascular surgery (EVAR) have improved 30 day mortality for elective abdominal aortic aneurysm (AAA) repair. It remains unknown whether this has translated into improvements in long-term survival, particularly because these factors have also encouraged the treatment of older patients with greater comorbidity. The aim of this study was to quantify how 5 year survival after elective AAA repair has changed over time. METHODS: A systematic review was performed identifying studies reporting 5 year survival after elective infrarenal AAA repair. An electronic search of the Embase and Medline databases was conducted to January 2014. Thirty-six studies, 60 study arms, and 107,814 patients were identified. Meta-analyses were conducted to determine 5 year survival and to report whether 5 year survival changed over time. RESULTS: Five-year survival was 69% (95% CI 67 to 71%, I(2) = 87%). Meta-regression on study midpoint showed no improvement in 5 year survival over the period 1969-2011 (log OR -0.001, 95% CI -0.014-0.012). Larger average aneurysm diameter was associated with poorer 5 year survival (adjusted log OR -0.058, 95% CI -0.095 to -0.021, I(2) = 85%). Older average patient age at surgery was associated with poorer 5 year survival (adjusted log OR -0.118, 95% CI -0.142 to -0.094, I(2) = 70%). After adjusting for average patient age, an improvement in 5 year survival over the period that these data spanned was obtained (adjusted log OR 0.027, 95% CI 0.012 to 0.042). CONCLUSION: Five-year survival remains poor after elective AAA repair despite advances in short-term outcomes and is associated with AAA diameter and patient age at the time of surgery. Age-adjusted survival appears to have improved; however, this cohort as a whole continues to have poor long-term survival. Research in this field should attempt to improve the life expectancy of patients with repaired AAA and to optimise patient selection

    Análise do meio físico para avaliação das limitações ambientais.

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    Embora semelhante do ponto de vista macroclimatico, ecossistemas contiguos podem apresentar profundas diferencas no aspectos microclimatico, bem como na disponibilidade de agua e envolvendo componentes de clima, de solo e vegetacao, faz com que as analises para estratificacao ambiental reunam um numero relativamente grande de informações que nem sempre estao sistematizadas. Por outro lado, o caracter interativo das relacoes existentes torna o processo complexo, demandando uma abordagem estratificacao de ambientes em termos de radiacao, disponibilidade de agua e nutrientes e de alguns fatores coadjuvantes. Em virtude de a grande maioria dos criterios utilizados para estratificacao de ambientes serem de uso corrente nos estudos de mapeamentos de solos, sugere-se a classe de solo como elemento estratificador de ambientes

    Students Engagement in School, Giftedness and Creativity: A literature review

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    Este E-Book reúne um conjunto de investigações apresentadas no “I Congresso Internacional Envolvimento dos Alunos na Escola: Perspetivas da Psicologia e Educação” (ICIEAE), organizado no âmbito do “Projeto PTDC/CPE-CED/114362/2009 - Envolvimento dos Alunos na Escola: Diferenciação e Promoção” (EAE-DP), financiado pela Fundação para a Ciência e a Tecnologia (FCT).Background: The importance of the construct “students engagement in school” (SES) has been recently pointed out in research and literature; however, there is a lack of studies about the relationship between this variable and personal variables, such as giftedness and creativity. These latter variables are conceptualized as a result of the convergence of personal and contextual variables, in which development and learning processes play a relevant role. Giftedness has been studied in its relationship with creativity, which, in turn, appears related to school context. Purpose: This article reviews the literature on the relation between students’ engagement in school and each of the variables of students’ giftedness and students’ creativity, as perceived by the students and their teachers. The importance of this relation arises from the idea that students perceived as having above average capacities, or as creative, have high motivation for learning and engagement in school. Giftedness has been studied in its relationship with creativity, which, in turn, appears related to school context. Method: In order to describe the state of art of student’s engagement in school and Giftedness and Creativity, we prepared a narrative review. Conclusions: Although studies on the relationship between creativity, giftedness and the students’ behavior require further research, the use of creativity as a teaching-learning instrument appears related to school satisfaction and students’ academic performance. The literature review highlights the need to develop research, particularly of quasi-experimental type, on the relationship between students’ engagement in school and the variables giftedness and creativity, as well as on its effects on academic achievement

    Cinética de sorção de fósforo em alguns solos de Minas Gerais.

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    Os processos cineticos e termodinamicos envolvidos nos mecanismos de troca de fosforo no sistema fase solida-solucao do solo sao ainda pouco conhecidos. O proposito do presente trabalho foi investigar o comportamento dinamico do fosforo em sistemas multifasicos. Como fase solida, foram utilizadas as fracoes argila de onze amostras de duas pedossequencias do Estado de Minas Gerais: uma com litologia variando em proporcoes de rochas peliticas e de tufito; outra de arenito e de basalto. E proposto um modelo cinetico para descrever a dinamica de sorcao do fosforo. Estimaram-se as constantes de taxa de reacao (ki, i = + ou - 1, + ou - 2) de primeira ordem, para as duas primeiras etapas consecutivas do mecanismo multiplo de reacao. Na maior parte das amostras, metade do fosforo adicionado (2 g de P kg -1 de solo) foi adsorvida entre 30 e 90 minutos de reacao. Como tendencia geral, a constante de equilibrio da primeira etapa do processo foi menor do que 1, indicando que a reacao reversa (dessorcao e termodinamicamente favorecida no equilibrio (variacao da energia livre padrao de Gibbs, delta G1 > 0), exceto para uma amostra. Nao houve correlacao significativa entre k e magnetizacao, o que reflete a influencia de rocha mafica no material de origem

    Creative climate and engagement of students in school: How do they relate?

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    Este E-Book reúne um conjunto de investigações apresentadas no “I Congresso Internacional Envolvimento dos Alunos na Escola: Perspetivas da Psicologia e Educação” (ICIEAE), organizado no âmbito do “Projeto PTDC/CPE-CED/114362/2009 - Envolvimento dos Alunos na Escola: Diferenciação e Promoção” (EAE-DP), financiado pela Fundação para a Ciência e a Tecnologia (FCT).Research has shown that creative climate has a constructive inluence on school engagement. The present study aims at understanding how creative climate relates to school engagement. A national sample of students responded to a questionnaire in class. The data collection instrument was the “Students’ engagement in school: A four-dimensional Scale” SES-4DS (Veiga, 2013). This scale revealed four dimensions: cognitive, affective, behavioural and agency. Measures of Perceived Creativity Climate (5 items) suggested by the literature were included. A total of 685 students participated in the study. We observed a higher proportion of girls (56.8%) than boys (43.2%). The creative climate-related items show a consistency of alpha 0.84 and a correlation of 0.38 with the total School Engagement Scale. The dimension more correlated with the creative climate is the cognitive one, suggesting that students who see school as a place that values their ideas process knowledge in a more intentional and motivated way. The variables age and number of school retentions contribute negatively to the engagement of students in the school. Some suggestions for the promotion of creative climate are presented in order to encourage the engagement of students in the school
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