Modelo de data mining para detecção de tumores em exames de rastreio

Dissertação para obtenção do grau de Mestre em Engenharia Informática

Global material analysis on phosphorus flows, supply horizon and impact assessment on phosphorus depletion

Different problems are daily discuss on environmental aspects such acid rain, eutrophication, global warming and an others problems. Rarely do we find some discussions about phosphorus problematic. Through the years the phosphorus as been a real problem and must be more discussed. On this thesis was done a global material flow analysis of phosphorus, based on data from the year 2004, the production of phosphate rock in that year was 18.9 million tones, almost this amount it was used as fertilizer on the soil and the plants only can uptake, on average, 20% of the input of fertilizer to grow up, the remainder is lost for the phosphorus soil. In the phosphorus soil there is equilibrium between the phosphorus available to uptake from the plants and the phosphorus associate with other compounds, this equilibrium depends of the kind of soil and is related with the soil pH. A reserve inventory was done and we have 15,000 million tones as reserve, the amount that is economical available. The reserve base is estimated in 47,000 million tones. The major reserves can be found in Morocco and Western Sahara, United Sates, China and South Africa. The reserve estimated in 2009 was 15,000 million tone of phosphate rock or 1,963 million tone of P. If every year the mined phosphate rock is around 22 Mt/yr (phosphorus production on 2008 USGS 2009), and each year the consumption of phosphorus increases because of the food demand, the reserves of phosphate rock will be finished in about 90 years, or maybe even less. About the value/impact assessment was done a qualitative analysis, if on the future we don’t have more phosphate rock to produce fertilizers, it is expected a drop on the crops yields, each depends of the kind of the soil and the impact on the humans feed and animal production will not be a relevant problem. We can recovery phosphorus from different waste streams such as ploughing crop residues back into the soil, Food processing plants and food retailers, Human and animal excreta, Meat and bone meal, Manure fibre, Sewage sludge and wastewater. Some of these examples are developed in the paper.

Logistic optimization in tourism networks

55th European Regional Science Association Congress, Lisbon, Portugal (25-28 August 2015).

Ancoragem: um programa de psicoeducação para familiares de doentes com esquizofrenia

Trabalho apresentado em XIII Congreso Internacional Galego-Portugués de Psicopedagoxía, Área 5 Familia, Escuela y Comunidad. Universidad da Coruña, 2 de Setembro de 2015.

O Balanced Scorecard: estudo do processo e mecanismos para ser uma ferramenta imprescindível no contexto organizacional

Mestrado em Contabilidade

The impact of financial disclosures in the measurement of notional interest rate swaps in the period of 2007-2012

Mestrado em Contabilidade

Proposta de um modelo de avaliação de websites de turismo de habitação

actividade de turismo de habitação tem crescido de forma sustentada ao longo dos últimos anos em Portugal e o recurso à internet como canal de comercialização deste serviço tem substituído gradualmente os restantes canais mais tradicionais. No entanto, esta generalização do recurso a websites, nesta e noutras áreas da actividade económica, não tem sido sempre sinónimo de qualidade, justificando assim a procura de sistemas de avaliação deste tipo de produto de software, que possam ser aplicados sistemática e eficazmente. Nesse sentido, foi desenvolvido este trabalho, no propósito de conseguir um modelo de avaliação de websites, específico para o turismo de habitação, na convicção de que para áreas específicas se exigem abordagens específicas. A pesquisa por modelos orientados para esta actividade não produziu qualquer resultado, ao contrário de outras áreas onde já existem modelos adequados, como sejam a área académica e outras. Daí a necessidade de conjugar ideias e conceitos mais genéricos, de fontes diversas, com elementos específicos de turismo de habitação, no intuito de os combinar e adequar aos objectivos deste trabalho. Assim, a partir de elementos da Norma ISO 9126; de conceitos de usabilidade, funcionalidade, credibilidade, e outros; da opção por uma abordagem de desempenho empresarial; de modelos já existentes, embora direccionados para outras áreas; e de um modelo exploratório de carácter empírico entretanto desenvolvido, foi concebido e implementado um modelo que se caracteriza no essencial, por ser estruturado em três níveis, contemplar um conjunto de trinta e oito atributos em avaliação, com maior incidência naqueles relacionados com aspectos que se considera terem maior influência no desempenho da actividade económica subjacente, e que tem uma ponderação variável do seu impacto no resultado final. No intuito de dar flexibilidade ao modelo e de contrariar a carga subjectiva resultante do processo de ponderação do impacto de cada atributo avaliado, foram implementados no modelo três cenários alternativos com ponderações distintas, cada um valorizando determinado tipo de atributos e desvalorizando outros. Naturalmente que, aquando da implementação do modelo exploratório foram já retiradas algumas conclusões sobre o panorama geral, todavia o modelo definitivo veio dar-lhes maior consistência e pormenor.

10 kVp rule – An anthropomorphic pelvis phantom imaging study using a CR system: impact on image quality and effective dose using AEC and manual mode

Purpose - This study aims to investigate the influence of tube potential (kVp) variation in relation to perceptual image quality and effective dose (E) for pelvis using automatic exposure control (AEC) and non-AEC in a Computed Radiography (CR) system. Methods and materials - To determine the effects of using AEC and non-AEC by applying the 10 kVp rule in two experiments using an anthropomorphic pelvis phantom. Images were acquired using 10 kVp increments (60–120 kVp) for both experiments. The first experiment, based on seven AEC combinations, produced 49 images. The mean mAs from each kVp increment were used as a baseline for the second experiment producing 35 images. A total of 84 images were produced and a panel of 5 experienced observers participated for the image scoring using the two alternative forced choice (2AFC) visual grading software. PCXMC software was used to estimate E. Results - A decrease in perceptual image quality as the kVp increases was observed both in non-AEC and AEC experiments, however no significant statistical differences (p > 0.05) were found. Image quality scores from all observers at 10 kVp increments for all mAs values using non-AEC mode demonstrates a better score up to 90 kVp. E results show a statistically significant decrease (p = 0.000) on the 75th quartile from 0.37 mSv at 60 kVp to 0.13 mSv at 120 kVp when applying the 10 kVp rule in non-AEC mode. Conclusion - Using the 10 kVp rule, no significant reduction in perceptual image quality is observed when increasing kVp whilst a marked and significant E reduction is observed.

Estudo da viabilidade técnica e económica da conversão para veículo elétrico

O veículo elétrico está cada vez mais presente no mercado de veículos de transporte e apresenta-se como uma solução sustentável para a mobilidade. Reduz as emissões de gases de efeito de estufa (GEE), ruído, e elimina a dependência do petróleo presente nos veículos convencionais. Numa altura em que o sector automóvel está em franca estagnação, e os preços dos combustíveis atingem máximos históricos, a conversão de veículos convencionais em veículos elétricos ganha especial relevo e apresenta-se como uma solução para alguns utilizadores ou mesmo uma oportunidade de negócio para algumas empresas. Este trabalho consiste no estudo da viabilidade técnica e económica da conversão de veículos convencionais em veículos elétricos. São identificados equipamentos essenciais para realizar uma conversão, equipamentos alternativos e alguns opcionais, modo como os equipamentos devem ser instalados no veículo, cuidados a ter durante a instalação e legislação a considerar. No critério técnico aborda-se o desempenho do veículo, velocidade máxima, autonomia, capacidade de aceleração em subidas e desempenho de cada velocidade da caixa. No critério económico o estudo focaliza-se no tempo de retorno do investimento, ponto de inviabilidade do investimento, proveitos num prazo de 10 anos de uso do veículo, e análise do impacto de alguns equipamentos alternativos no investimento total. Abordam-se todos os aspetos a ter em consideração para que se realize uma conversão com sucesso e em simultâneo realiza-se uma conversão tipo do veículo do qual sou proprietário, um Volkswagen Golf 2 de 1988. Em sintonia com os objetivos deste trabalho, demonstra-se que o veículo elétrico é uma boa opção para utilizações citadinas, e que a tecnologia já esta suficientemente madura para este tipo de utilizações, o investimento na conversão é facilmente amortizável e portanto antecipa-se uma era onde prosperarão os veículos elétricos.

Impact on human health of particulate matter emitted from burnings in the Brazilian Amazon region

OBJECTIVE: To analyze the impact on human health of exposure to particulate matter emitted from burnings in the Brazilian Amazon region. METHODS: This was an ecological study using an environmental exposure indicator presented as the percentage of annual hours (AH%) of PM2.5 above 80 μg/m3. The outcome variables were the rates of hospitalization due to respiratory disease among children, the elderly and the intermediate age group, and due to childbirth. Data were obtained from the National Space Research Institute and the Ministry of Health for all of the microregions of the Brazilian Amazon region, for the years 2004 and 2005. Multiple regression models for the outcome variables in relation to the predictive variable AH% of PM2.5 above 80 μg/m3 were analyzed. The Human Development Index (HDI) and mean number of complete blood counts per 100 inhabitants in the Brazilian Amazon region were the control variables in the regression analyses. RESULTS: The association of the exposure indicator (AH%) was higher for the elderly than for other age groups (β = 0.10). For each 1% increase in the exposure indicator there was an increase of 8% in child hospitalization, 10% in hospitalization of the elderly, and 5% for the intermediate age group, even after controlling for HDI and mean number of complete blood counts. No association was found between the AH% and hospitalization due to childbirth. CONCLUSIONS: The indicator of atmospheric pollution showed an association with occurrences of respiratory diseases in the Brazilian Amazon region, especially in the more vulnerable age groups. This indicator may be used to assess the effects of forest burning on human health.

Should the U.S. adapt to the world? The first debate on american exceptionalism and its impact on the founding of the United States

This paper aims at putting into perspective the recent, post 9/11 debate on the United States‘ alleged exceptionalism and its impact on the definition of American foreign policy. It reminds the readers that the United States was born as a result of a similar debate, at a time when a crucial choice for its future was to be made. Indeed, the Founding Fathers discarded the revolutionary idea that America was altogether different from other (European) nations and, as such, could succeed in saving republicanism and concentrate on domestic affairs. As Gordon Wood and Harvey Mansfield have shown, the 1787 version of republicanism stood as a departure from its earlier version, and such a change was necessary to the creation of a full-fledged federation, therefore paving the way to the current powerful Federal Republic. The early failure of the exceptionalist creed did not cause its disappearance, as the contemporary form of exceptionalism demonstrates, but created conditions that made an enduring and powerful influence very difficult.

Increasing source to image distance for AP pelvis imaging: impact on radiation dose and image quality

Aim - A quantative primary study to determine whether increasing source to image distance (SID), with and without the use of automatic exposure control (AEC) for antero-posterior (AP) pelvis imaging, reduces dose whilst still producing an image of diagnostic quality. Methods - Using a computed radiography (CR) system, an anthropomorphic pelvic phantom was positioned for an AP examination using the table bucky. SID was initially set at 110 cm, with tube potential set at a constant 75 kVp, with two outer chambers selected and a fine focal spot of 0.6 mm. SID was then varied from 90 cm to 140 cm with two exposures made at each 5 cm interval, one using the AEC and another with a constant 16 mAs derived from the initial exposure. Effective dose (E) and entrance surface dose (ESD) were calculated for each acquisition. Seven experienced observers blindly graded image quality using a 5-point Likert scale and 2 Alternative Forced Choice software. Signal-to-Noise Ratio (SNR) was calculated for comparison. For each acquisition, femoral head diameter was also measured for magnification indication. Results - Results demonstrated that when increasing SID from 110 cm to 140 cm, both E and ESD reduced by 3.7% and 17.3% respectively when using AEC and 50.13% and 41.79% respectively, when the constant mAs was used. No significant statistical (T-test) difference (p = 0.967) between image quality was detected when increasing SID, with an intra-observer correlation of 0.77 (95% confidence level). SNR reduced slightly for both AEC (38%) and no AEC (36%) with increasing SID. Conclusion - For CR, increasing SID significantly reduces both E and ESD for AP pelvis imaging without adversely affecting image quality.

Environmental impact caused by fungal and particle contamination of Portuguese swine

Social concerns for environmental impact on air, water and soil pollution have grown along with the accelerated growth of pig production. This study intends to characterize air contamination caused by fungi and particles in swine production, and, additionally, to conclude about their eventual environmental impact. Fiftysix air samples of 50 litters were collected through impaction method. Air sampling and particle matter concentration were performed in indoor and also outdoor premises. Simultaneously, temperature and relative humidity were monitored according to the International Standard ISO 7726 – 1998. Aspergillus versicolor presents the highest indoor spore counts (>2000 CFU/m3) and the highest overall prevalence (40.5%), followed by Scopulariopsis brevicaulis (17.0%) and Penicillium sp. (14.1%). All the swine farms showed indoor fungal species different from the ones identified outdoors and the most frequent genera were also different from the ones indoors. The distribution of particle size showed the same tendency in all swine farms (higher concentration values in PM5 and PM10 sizes). Through the ratio between the indoor and outdoor values, it was possible to conclude that CFU/m3 and particles presented an eventual impact in outdoor measurements.

Mammography equipment design: impact on radiographers’ practice

Objectives - Identify radiographers’ postures during frequent mammography procedures related to the mammography equipment and patient characteristics. Methods - A postural task analysis was performed using images acquired during the simulation of mammography positioning procedures. Simulations included craniocaudal/(CC) and mediolateral-oblique/(MLO) positioning in three different settings: radiographers and patients with similar statures, radiographers smaller than the patients and radiographers taller than the patients. Measurements of postural angles were performed by two raters using adequate software and classified according to the European Standard EN1005-4:2005 + A1:2008. Results - The simulations revealed that the most awkward posture in mammography is during the positioning of MLO projection in short-stature patients. Postures identified as causing work-related musculoskeletal disorder (WRMSD) risk were neck extension, arms elevated and the back stooped, presenting angles of 87.2, 118.6 and 63.6, respectively. If radiographers were taller than patients, then the trunk and arm postures were not acceptable. Conclusions - Working in a mammography room leads to awkward postures that can have an impact on radiographers’ health, namely WRMSDs. The results in this study showed that there are non-acceptable postures associated with frequent working procedures in mammography. MLO is the most demanding procedure for radiographer postures and may be related to WRMSDs. Mammography devices should be redesigned considering adjustability for radiographers. Main Messages: • Mammography constraints for radiographers in mammography procedures have not been well studied. • Performing mammography leads to awkward postures that can impact radiographers’ health. • MLO, the most demanding procedure for radiographers, is possibly related to WRMSDs.

Impact of academic exposure on health status of university students

OBJECTIVE: To assess the impact of academic life on health status of university students. METHODS: Longitudinal study including 154 undergraduate students from the Universidade de Aveiro, Portugal, with at least two years of follow-up observations. Sociodemographic and behavioral characteristics were collected using questionnaires. Students' weight, height, blood pressure, serum glucose, serum lipids and serum homocysteine levels were measured. Regression analysis was performed using linear mixed-effect models, allowing for random effects at the participant level. RESULTS: A higher rate of dyslipidemia (44.0% vs. 28.6%), overweight (16.3% vs. 12.5%) and smoking (19.3% vs. 0.0%) was found among students exposed to the academic life when compared to freshmen. Physical inactivity was about 80%. Total cholesterol, high density lipoprotein-cholesterol (HDL-C), triglycerides, systolic blood pressure, and physical activity levels were significantly associated with gender (p<0.001). Academic exposure was associated with increased low density lipoprotein-cholesterol (LDL-C) levels (about 1.12 times), and marginally with total cholesterol levels (p=0.041). CONCLUSIONS: High education level does not seem to have a protective effect favoring a healthier lifestyle and being enrolled in health-related areas does not seem either to positively affect students' behaviors. Increased risk factors for non-transmissible diseases in university students raise concerns about their well-being. These results should support the implementation of health promotion and prevention programs at universities.