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- Bioestatística com SPSS: notas de apoioPublication . Serranho, Pedro; Ramos, Maria do RosárioNotas de apoio ao curso de "Biostestatística com SPSS" leccionado pelos Prof. Doutor Francisco Caramelo (Universidade de Coimbra), Prof. Doutora Maria Rosário Ramos e Prof. Doutor Pedro Serranho.
- Acid phosphatase, some genetic polymorphism and obesity risk factors in adult womenPublication . Carolino, E.; Oliveira, T.; Silva, A. P.; Carvalho, R; Bicho, M.Recent works point out to a relation between some genetic factors and the predisposition for obesity. We believe, therefore, to be relevant to conduct this kind of study in the Portuguese population. In the present work the following genetic factors are considered: Haptoglobin phenotype, the Acid Phosphatasehenotype and two blood group systems, the MN System and the Lewis System. In addition, it was also considered one demographic factor, age, and one enzymatic activity, the Acid Phosphatase Activity. Haptoglobin (Hp) is a hemoglobin-binding protein of the immune system expressed by a genetic polymorphism with three major phenotypes. This protein is associated in some works with susceptibility for common pathological situations, such as some disorders related with obesity. The Acid phosphatase, more precisely the Acid phosphatase locus 1 (ACP1), is a highly polymorphic enzyme that has an important role in flavoenzyme activity and in the control of insulin receptor activity. High ACP1 activity was positively associated with high glycemic levels and with high body mass index (BMI) values. The MN blood system is a blood group system with three phenotypes each one showing different associations with some diseases, including some related with obesity. Finally, the Lewis System was focused on a single locus with two antigens, Le a and Le b. Confirming this characteristic as a genetic marker of obesity may contribute to the explanation of individual differences in the prevalence of obesity. The group under study involves 85 Portuguese adult women with complete data for all variables, taken from a data base with 714 subjects from the Genetic Laboratory, Centre of Endocrinology and Metabolism of University of Lisbon. The aim of the study is to explore and examine the relationship between the weight categories and the explanatory variables, with emphasis on risk for obesity. Therefore, an ordinal regression model was tried, considering as the regressor variables the Haptoglobin phenotype, Acid phosphatase (ACP1) phenotype, MN blood group system, Lewis system, the enzymatic activity of ACP1, age and some association effects between these factors. Some significant main effects were found at a 5% significance level: the phenotypeLe(a-b+) of Lewis System (p-value=0,021) and age (p-value=0,002). The phenotype Le(a-b+) of Lewis System is associated with a decreased risk for obesity (odds ratio 0,139; CI95%(0,016; 0,754)); age (as expected) is associated with an increased risk for obesity (odds ratio 1,11; CI95%(1,038; 1,190))
- Ensino superior a distância e o desenvolvimento de competências profissionais: uma análise com base nas perceções dos diplomadosPublication . Henriques, Susana; Neves, Claudia; Silva, Ana Paula; Abrantes, Pedro; Bäckström, Bárbara; Falé, Isabel; Jacquinet, Marc; Magano, Olga; Ramos, Maria do RosárioQuem são os estudantes que optam pela Educação Superior a Distância ? Quais as suas expetativas e grau de satisfação com os cursos nesta modalidade ? Qual o impacto do curso na vida profissional e pessoal do estudante da UAb ? O presente artigo centra-se nestas questões, seguindo um enquadramento teórico que mobiliza estudos sobre a procura de respostas para novos públicos e novas necessidades nas sociedades atuais. O desenho metodológico seguiu a aplicação de um questionário, desenhado no âmbito do Observatório dos Percursos Profissionais e de Vida dos Diplomados da Universidade Aberta, aos estudantes que terminaram a licenciatura em 2014 e 2015. Os resultados remetem para uma satisfação global com a realização da licenciatura online, na medida em que revelam conforto no uso da plataforma e reconhecem vantagens no regime de aprendizagem. Destaca-se a valorização do prestígio social associado ao diploma de ensino superior. Concluímos que a pesquisa sobre o fenómeno da empregabilidade no ensino superior precisa de mais desenvolvimento. Os estudantes adultos apresentam um conjunto de necessidades diferenciadas, sobretudo relacionadas com a aquisição de competências para melhorar as suas condições profissionais, de empregabilidade e o desenvolvimento das suas carreiras. Os dados deste estudo reforçam a ideia de educação ao longo da vida associada ao ensino a distância como importante forma de desenvolvimento e aquisição não só de conhecimentos, como também, de competências transversais fundamentais a todos os contextos da vida e para a mobilidade profissional.
- Cidadania ambiental ativa de jovens na prevenção de resíduos: um estudo de caso em cursos profissionaisPublication . Rosário, Patrícia; Martinho, Ana Paula; Ramos, Maria do Rosário; Portela, Célia; Bagagem, TeresaO presente estudo teve como objetivo desenvolver um projeto de cidadania ambiental para que os jovens de cursos profissionais se tornem mais responsáveis no consumo e na prevenção de resíduos e sejam também agentes de mudança. Em todas estas atividades, os jovens estudantes foram participativos e sensíveis a todos as questões abordadas. Foi aplicado um conjunto de instrumentos participativos, que os tornou mais ativos e mais sensíveis para as questões de consumo e de prevenção de resíduos. Para além da aplicação de inquéritos por questionário e a realização de um debate, foi também aplicada a realização de um workshop participativo, onde os estudantes elaborarem um plano de ação com um conjunto de medidas de prevenção de resíduos para os locais onde costumam frequentar e ajustadas à sua futura vida profissional. Foi feita uma abordagem predominantemente qualitativa, com a aplicação de questionários e com a utilização da técnica de observador participante. Os dados recolhidos nos questionários serviram para fazer uma análise quantitativa com a aplicação de testes estatísticos, a fim de traçar o perfil destes alunos e explorar relações relativamente às dimensões Conhecimentos, Atitudes e Comportamentos. Este projeto recorreu a diferentes formas de avaliação que contribuíram para se realizar uma avaliação cuidada e aprofundada do projeto. Este trabalho apresenta um aspeto inovador por ter sido desenvolvido em cursos profissionais, não se tendo encontrado outros trabalhos desenvolvidos neste público-alvo. Assim, entende-se que a aplicação do projeto em outras escolas com cursos profissionais pode ajudar a sensibilizar estes jovens que estão muito próximo de entrarem no mercado do trabalho para as questões da prevenção de resíduos e da sustentabilidade.
- Statistical models for categorical data: brief review for applications in ecologyPublication . Ramos, Maria do Rosário; Oliveira, Manuela M.; Borges, José G.; McDill, Marc E.A brief review of statistical models for prediction of categorical data is presented, with emphasis on the binary type. Several methods have been adopted to build predictive models for binary and other types of categorical data and response variables. The focus here is on generalized linear models and generalized additive models, widely applied in problems in Ecology, when the goal is to fit a model to data of presence/absence type or any other categorical response.The estimation methods used for generalized linear models and generalized additive models as well its statistical properties are discussed. Some examples in ecology are addressed.
- Haptoglobin, acid phosphatase and demographic factors: obesity riskPublication . Ramos, Maria do Rosário; Carolino, Elisabete; Oliveira, Teresa; Silva, A. P.; Carvalho, R.; Bicho, M.The aim of this work is to study the risk of obesity posed by two genetic factors: haptoglobin phenotype and acid phosphatase phenotype, one enzymatic activity: acid phosphatase activity (ACP1), age and gender. Haptoglobin (Hp) is a protein of the immune system, and three phenotypes of Hp are found in humans: Hp1-1, Hp2-1, and Hp2-2. This protein is associated with a susceptibility to common pathological conditions, such as obesity. ACP1 is an intracellular enzyme The phenotypes of ACP1 (AA, AB, AC, BB, BC, CC) are also considered. We took a sample of 127 subjects with complete data from 714 registers. Since we intend to identify risk factors for obesity, an ordinal regression model is adjusted, using the Body Mass Index, BMI, to define weight categories. Haptoglobin phenotype, enzymatic activity of ACP1, acid phosphatase phenotype, age and gender are considered as regressor variables. We found three factors associated with an increased risk of obesity: phenotype Hp2-1 of haptoglobin (estimated odds ratio OR 11.54), phenotype AA of acid phosphatase (OR 33.788) and age (OR 1.39). The interaction between phenotype Hp2-1 and phenotype AC is associated with a decreased risk of obesity (OR 0.032); The interaction between phenotype AA and ACP1 activity is associated with a decreased risk of obesity (OR 0.954).
- Uncovering abnormal water consumption patterns for sustainability’s sake: a statistical approachPublication . Borges, Ana; Cordeiro, Clara; Ramos, Maria do RosárioMonitoring domestic water usage may help the water utilities uncover abnormal water consumption. In this context, it is necessary to improve and develop tools based on data analysis of households’ meter readings. This study contributes to this goal by using a statistical methodology that detects abnormal water consumption patterns, namely, significant increases or decreases. This approach relies on a combination of methods that analyse billed water consumption time series. The first step is to decompose the time series using Seasonal-Trend decomposition based on Loess. Next, breakpoint analysis is performed on the seasonally adjusted time series to look for changes in the pattern over time. Afterwards, the Mann–Kendall test and Sen’s slope estimator are applied to assess whether there are significant increases or decreases in water consumption. The strategy is applied to water consumption data from the Algarve, Portugal, successfully detecting breakpoints associated with significant increasing or decreasing trends.
- A strategy to assess water meter performancePublication . Cordeiro, Clara; Borges, Ana; Ramos, Maria do RosárioApparent water losses can be problematic to water companies’ revenues. This type of loss is very difficult to detect and quantify and is often associated with water meter anomalies. This study was motivated by a water company’s challenge that links a decrease in water consumption to water meters’ malfunction. The aim is to develop a strategy to detect decreasing water usage patterns, contributing to meter performance assessment. The basis of the approach is a combination of statistical methods. First, the time series of billed water consumption is decomposed using Seasonal-Trend decomposition based on Loess. Next, breakpoint analysis is performed on the seasonally adjusted time series. After that, the Mann–Kendall test and Sen’s slope estimator are used to analyze periods of progressive decrease changes in water consumption, defined by breakpoints. A quantitative indicator of this change is proposed. The strategy was successfully applied to eight-time series of water consumption from the Algarve, Portugal.
- Improving forecasting by resampling STL decompositionPublication . Cordeiro, Clara; Ramos, Maria do Rosário; Neves, M. ManuelaThe development of new forecasting algorithms has shown an increasing interest due to the emerging of new fields of application like machine learning and forecasting competitions. Although initially intended for independent random variables, bootstrap methods can be successfully applied to time series. The Boot.EXPOS procedure, which combines bootstrap and exponential smoothing methods, has shown promising results for forecasting. This work proposes a new approach to forecasting, which is briefly described as follows: using Seasonal-Trend decomposition by Loess (STL), the best STL fit is selected by testing all possible combinations of parameters. The best combination of smoothing parameters is chosen based on an accuracy measure. The time series is then decomposed into components according to the best STL fit. The Boot.EXPOS procedure is employed to forecast the seasonal component and the seasonally adjusted time series. These forecasts are aggregated to obtain a final forecast. The performance of this combined forecast is evaluated using real datasets and compared with other established forecasting methods.
- Environmental Management Systems (EMS) implementation processes and practices in european higher education institutions: top-down versus participatory approachesPublication . Disterheft, Antje; Caeiro, Sandra; Ramos, Maria do Rosário; Azeiteiro, UlissesEnvironmental Management Systems (EMS) have been implemented on a large scale to improve companies’ environmental performance and to certify their achievements. More recently, universities are following this trend, which has been brought forward by the debate about campus sustainability. This empirical international research investigates EMS development and implementation processes in universities around Europe, providing an overview about European higher education institutions with EMS implemented at their campuses, and focuses on a comparison of top-down versus participatory implementation approaches. In addition to regional differences, this article discusses in which aspects an EMS at the campus can be seen as a tool that goes beyond operational aspects to tackle campus sustainability. Furthermore, it provides implications for the professional practice.