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Objetivo. A maconha apresentou estimativa de 13 milhões de casos de dependência em 2010, sendo este quadro fortemente associado ao uso abusivo dessa planta. Diante disso, este estudo busca avaliar os impactos do uso e abuso de maconha em adolescentes e adultos jovens do ponto de vista neuropsiquiátrico, da mortalidade e da afecção de outros sistemas orgânicos. Método. É uma revisão sistemática, baseada no método PRISMA. A seleção da população baseou-se em artigos que abordaram pessoas com faixa etária correspondente à adolescência, jovem e/ou adulta jovem, segundo a definição de adolescência prescrita pela Organização Mundial da Saúde (OMS) e segundo o Estatuto da Juventude Brasileiro em uso de maconha não medicinal. Sem restrição de sexo, raça, cor ou nível socioeconômico. Resultados. O uso de maconha não medicinal, caracterizado por seu consumo pelo fumo ou vaporização, apresentou uma série de alterações desde neurais a fisiológicas gerais. Foi observado amplo efeito do uso da Cannabis sativa com aparente efeito dose dependente no campo da afecção dos domínios neurocognitivos, aprendizado verbal, memória e atenção, função psicomotora, impulsividade cognitiva e flexibilidade cognitiva. Apesar do efeito ser aparentemente atribuído à maior dosagem de consumo, o uso em pequenas doses também foi associado a efeitos deletérios em alguns pacientes com transtorno psicótico subjacente. Conclusão. uso não medicinal da Cannabis sativa apresenta relação significativa com distúrbios neuropsiquiátricos nas esferas da função motora e perceptual, função executiva, cognição social e aprendizado e memória, transtornos de humor e psicóticos, transtornos da função executiva (inibição social) e distúrbios cardiovasculares.

Rationale and Objectives The objective of this study was to evaluate the ultrasound features of thyroid nodules and their association with malignancy, focusing on establishing feature-oriented ultrasound criteria to determine proper management of a thyroid nodule. Materials and Methods A sample of 379 thyroid nodules were biopsied (from a total of 357 patients aged 59.8 ± 14.8 years) and 300 were included in the final study (271 benign nodules and 29 malignant ones). Ultrasound features were recorded for each nodule: size, echogenicity, homogeneity, contours, shape, texture, peripheral halo, calcifications, and the presence of adenopathy. Statistical analysis of the data was performed using the Mann-Whitney U test and chi-square test. The sensitivity and the specificity of variables seen to have a statistically significant association with the malignancy of nodules were assessed and a logistic regression was performed. Results A taller-than-wide shape, an ill-defined contour, the presence of a halo, microcalcifications, and adenopathy were found to have a statistically significant relationship (P Conclusions The ultrasound features of thyroid nodules alone do not allow the radiologist to make a confident diagnosis regarding the malignancy of a nodule without performing a biopsy. However, a nodule showing a taller-than-wide shape, microcalcifications, a peripheral halo, an ill-defined contour, or associated adenopathy should be considered for cytology.

The scientific community is increasingly concerned about the presence of pharmaceuticals in the aquatic environment, which is a consequence of their high consumption and inefficient removal by wastewater-treatment plants. The search for an effective and sustainable tertiary treatment is therefore needed to enhance their removal. For this purpose, the combination of electrochemical and adsorption processes into three-dimensional (3D) electrochemical systems has been proposed. In this study, a 3D system was studied to remove carbamazepine, an antiepileptic, consumed in high doses and very persistent in the environment. The influences of the following parameters on its removal were evaluated: anode and cathode materials and distance between them, electrolyte (NaCl) concentration and pH, and the (carbon-based) adsorbent material used as the particulate electrode. The obtained results demonstrated that the introduction of the particulate electrode improved the removal efficiency. This can be attributed to the simultaneous occurrence of different phenomena, such as adsorption/electrosorption, electrocoagulation, oxidation, and catalytic degradation.

This paper describes the process of creating a Web application to support the tutoring system of a higher education institution. Application that allows the registration of interaction sessions between tutors and tutored, as well as the fill of questionnaires, both by the Students and by the Teachers Tutors. All this information helps the Student Provider to make decisions and define interventions, as well as in the preparation of the annual report to be presented to the academic direction. After deploying this application the mentoring program had an exponential increase the level of participation/membership, both by tutors and by tutored.

The objective of this study was to evaluate the ultrasound features of thyroid nodules and their association with malignancy, focusing on establishing feature-oriented ultrasound criteria to determine proper management of a thyroid nodule.A sample of 379 thyroid nodules were biopsied (from a total of 357 patients aged 59.8 ± 14.8 years) and 300 were included in the final study (271 benign nodules and 29 malignant ones). Ultrasound features were recorded for each nodule: size, echogenicity, homogeneity, contours, shape, texture, peripheral halo, calcifications, and the presence of adenopathy. Statistical analysis of the data was performed using the Mann-Whitney U test and chi-square test. The sensitivity and the specificity of variables seen to have a statistically significant association with the malignancy of nodules were assessed and a logistic regression was performed.A taller-than-wide shape, an ill-defined contour, the presence of a halo, microcalcifications, and adenopathy were found to have a statistically significant relationship (P 0.05) with malignancy, although with a low sensitivity and a high specificity. The presence of at least one suspicious feature yields great sensitivity (89.7%) in detecting malignant disease.The ultrasound features of thyroid nodules alone do not allow the radiologist to make a confident diagnosis regarding the malignancy of a nodule without performing a biopsy. However, a nodule showing a taller-than-wide shape, microcalcifications, a peripheral halo, an ill-defined contour, or associated adenopathy should be considered for cytology.

One-dimensional Haldane gap materials, such as the rare earth barium chain nickelates, have received great interest due to their vibrant one-dimensional spin antiferromagnetic character and unique structure. Herein we report how these 1D structural features can also be highly beneficial for thermoelectric applications by analysis of the system Ca

Mestrado em Engenharia Mecânica Submitted by Carla Jesus (cjesus@ua.pt) on 2017-12-05T10:52:02Z No. of bitstreams: 1 45612.pdf: 28746624 bytes, checksum: 504a916341c673b2d4387f083ab37832 (MD5) Made available in DSpace on 2017-12-05T10:52:03Z (GMT). No. of bitstreams: 1 45612.pdf: 28746624 bytes, checksum: 504a916341c673b2d4387f083ab37832 (MD5) Previous issue date: 2015

Mestrado em Engenharia Mecânica This work is dedicated to the characterization of thermoelectric materials, as well as the simulation of their application and optimization by using a mathematical model. Thermoelectric generators are commonly used in space exploration for many decades, however their application can be extended to the recovery of exhaust gases in automobiles and industrial processes as well as the powering of different types of remote sensors. In this work, the BaGd2NiO5 material and its doping states with Ca were studied for the first time in terms of their thermoelectric properties such as Seebeck coefficient, thermal conductivity and electrical conductivity. A mathematical model was also developed to simulate the application performance of any thermoelectric material for various working conditions. After the experimental validation of the model it was used to simulate the performance of Ca0.15BaGd1.85NiO5 compound, which presented the best thermoelectric properties. The numerical simulations showed that the performance of a thermoelectric generator with this material would be as better as larger is the temperature difference that the module is subjected and as greater is the heat transfer from hot and cold sources to the thermoelectric generator. The electrical conductivity of Ca0.15BaGd1.85NiO5 is the main reason for its low viability since the conversion efficiency was much lower than 1% and the power output was also reduced. This work revealed that the doping of BaGd2NiO5 with Ca can improve its thermoelectric properties, such as the increasing of the electrical conductivity and the reduction of the thermal conductivity. Moreover, the optimization of the application showed to be important in terms of increasing the performance and reducing the material. The mathematical model permitted to conclude that the optimum thickness of the thermoelements will be as smaller as larger is the heat transfer coefficient by convection of the hot and cold fluids. The simulations with the mathematical were also useful to conclude that a generator with thermoelectric properties of Ca0.15BaGd1.85NiO5 could have a wide applicability if its electrical conductivity could be a hundred times greater than the current value. Este trabalho é dedicado à caracterização de materiais termoeléctricos, bem como a simulação da sua aplicação e otimização utilizando um modelo matemático. Os geradores termoeléctricos são utilizados com frequência na exploração espacial à várias décadas, no entanto a sua aplicação pode ser alargada à recuperação de gases de escape em automóveis e processos industriais, bem como na alimentação de diferentes tipos de sensores remotos. No presente trabalho, o material BaGd2NiO5 e seus estados de dopagem com Ca foram estudados pela primeira vez a nível das suas propriedades termoeléctricas tais como coeficiente de Seebeck, condutividade térmica e condutividade eléctrica. Um modelo matemático foi desenvolvido de forma a simular o desempenho da aplicação de um determinado material termoeléctrico para várias condições de trabalho. Após a validação experimental do modelo, o mesmo foi utilizado para simular o desempenho do composto Ca0.15BaGd1.85NiO5, o qual apresentou as melhores propriedades termoeléctricas. As simulações numéricas permitiram concluir que o desempenho de um gerador termoeléctrico com este tipo de material seria tanto melhor quanto maior for a diferença de temperaturas a que está sujeito e quanto maior for o coeficiente de transferência de calor por convecção das fontes quente e fria. A baixa condutividade eléctrica do material Ca0.15BaGd1.85NiO5 fez com que a viabilidade da sua utilização apresente algumas dificuldades uma vez que a sua eficiência será inferior a 1%, sendo a potência produzida igualmente reduzida. Este trabalho permitiu concluir que a dopagem do material BaGd2NiO5 com Ca poderá melhorar as suas propriedades termoeléctricas, nomeadamente com o aumento da condutividade eléctrica e com a redução da condutividade térmica. Por outro lado, a otimização da aplicação mostrou ser relevante em termos de aumento do desempenho e redução de material. O modelo matemático permitiu concluir que a espessura ótima dos elementos termoeléctricos será tanto menor quanto maior for o coeficiente de transferência de calor por convecção dos fluídos quente e frio. A partir do modelo matemático foi ainda possível concluir que um gerador com as propriedades de Ca0.15BaGd1.85NiO5 poderia ter uma grande aplicabilidade e se a sua condutividade eléctrica fosse cem vezes superior ao valor atual.

Pancreatic dorsal agenesis (PDA) is a rare congenital anomaly, usually asymptomatic, that can present with abdominal pain, pancreatitis, diabetes mellitus and jaundice. Pancreatic tumours in PDA background are extremely rare, and when they occur are mainly pancreatic ductal adenocarcinoma. We present a case of a 48-year-old female patient with incidental detection of a 26×20 mm nodular lesion of the cephalic pancreas on ultrasound. Surgery was performed and gross examination revealed PDA with a tumour developed around the Wirsung duct. Histology showed a neuroendocrine tumour G1 with neural and vascular invasion. Two and half years later, the patient is alive and without tumour relapse. Awareness of the association of PDA and pancreatic tumours is fundamental in order to develop personalised follow-up programmes.

Submitted by Ana Rebelo (amsr@isep.ipp.pt) on 2015-02-23T13:01:04Z No. of bitstreams: 1 DM_CarlosFerreira_2014_MEESE.pdf: 4711185 bytes, checksum: cc3eae710a3ed3b7fc2d3380bbab1d15 (MD5) Approved for entry into archive by Ana Rebelo (amsr@isep.ipp.pt) on 2015-02-23T13:01:34Z (GMT) No. of bitstreams: 1 DM_CarlosFerreira_2014_MEESE.pdf: 4711185 bytes, checksum: cc3eae710a3ed3b7fc2d3380bbab1d15 (MD5) Made available in DSpace on 2015-02-23T13:01:35Z (GMT). No. of bitstreams: 1 DM_CarlosFerreira_2014_MEESE.pdf: 4711185 bytes, checksum: cc3eae710a3ed3b7fc2d3380bbab1d15 (MD5) Previous issue date: 2014

Dissertação de mestrado integrado em Engenharia Civil, As estruturas de alvenaria são a solução construtiva mais antiga e ainda hoje representam um importante sistema construtivo no parque habitacional português. Estas, devido à sua idade e falta de manutenção carecem de intervenções estruturais. A fim de melhorar o comportamento das alvenarias, em especial os problemas associados às cargas laterais, podem ser aplicadas diversas técnicas. Para este fim, na presente pesquisa vai ter-se como base o sistema ARMO, constituído por ARMO-crete. O presente trabalho de investigação tem como principal foco proporcionar um método que permita caracterizar a interface entre dois materiais distintos, neste caso entre o ARMO-crete e um dos tipos de alvenaria mais usuais em Portugal, o granito. De forma a caracterizar esta interface, começou-se por realizar uma análise ao material de reforço. Para tal realizaram-se diversos ensaios de flexão, compressão e resistência à tracção, para assim se conhecerem melhor as propriedades mecânicas dos materiais a estudar. O núcleo desta dissertação é composto essencialmente por uma caracterização experimental da interface entre os objectos e ainda por uma análise da rugosidade do material de alvenaria usado. Para tal realizaram-se ensaios experimentais de corte para três diferentes tipos de granito, obtendo-se o critério de rotura para estados de tensão no plano. No que diz respeito à análise da rugosidade foram realizados dois tipos de ensaio diferentes com vista a uma comparação entre eles. Deste modo, realizou-se ensaios recorrendo a um sensor laser e ainda recorrendo a fotografia digital. Por último pretendeu-se efectuar um estudo da influência da rugosidade sobre a interface entre materiais de substrato e de reforço, por intermédio dos resultados obtidos nos ensaios de corte., The masonry structures are the oldest constructive solution and even today represents an important building system on Portuguese habitational park. This, because of their age and lack of maintenance require structural interventions. In order to improve the performance of the masonry, in particular the problems associated with the lateral loads, different techniques may be applied. For this purpose, in this study will be taken based on the ARMO system made by ARMO-crete. This research work is mainly focused on providing a method that allows to characterize the interface between two different materials, in this case, between the ARMO-crete and one of the most common types pf masonry in Portugal, granite. In order to characterize this interface, it was first performed an analysis of the reinforcing material. For this, there have been made many trials of flexion, compression and tensile strength, thereby to better understand the mechanical properties of the material to study. The heart of this dissertation is composed mostly by an experimental characterization of the interface between the objects and also by an analysis of the roughness of masonry material used. Therefor shear experimental trials were carried out for three different types of granite, obtaining the rupture criterion for tension states on the plan. About the analysis of two different types of roughness, experiments were carried out with the aim of comparing them. Thereby, assays were carried out using a laser sensor and also using digital photography. Finally, it was intend to conduct a study of the influence of roughness on the interface between the substrate and reinforcement materials through the test results obtained on the cutting trials.

Health information technologies are becoming more common in the health care practice and electronic health records are considered a keystone. However, there is also an increasing concern of keeping secure the patient's data and assure privacy. The aim of this paper was to perceive and illustrate by what means Portugal, the Netherlands and the United Kingdom intend to keep their electronic health information secure and assure patient privacy. Based in official documents collected in the health department's websites of the three selected countries, it was used an analysis model framework previously published that includes 14 topic areas of health records security policies. Analyzing 14 official documents of the subject countries, it was possible to design an illustrative table of the 14 topic areas regarding security and privacy issues. This table allows comparing the different security measures adopted by the three countries to keep the patient privacy, such as a network security and access control to system resources. Given the analysis of the official documents of the three countries, it was verified that none of them has a very thorough approach of how electronic health records should be implemented with regard to privacy and security.

Mestrado em Engenharia Civil Como se sabe, os elementos de compartimentação são um obstáculo à passagem do fogo, limitando a propagação do mesmo no interior de um edifício. O conhecimento da resistência ao fogo destes elementos permite avaliar o seu desempenho numa situação de incêndio. É importante que os elementos de compartimentação mantenham as suas funções durante um certo período de tempo para possibilitar a evacuação das pessoas e a intervenção dos bombeiros. Esta dissertação encontra-se dividida em quatro partes. A primeira centra-se na regulamentação sobre resistência ao fogo. Na segunda parte é apresentado o comportamento térmico de alguns materiais e produtos de construção mais utilizados actualmente. Na terceira parte é descrito três dos ensaios realizados no LERF, Laboratório de Estruturas e Resistência ao Fogo da Universidade de Aveiro. Por fim, na quarta parte, é descrito uma modelação numérica realizada a uma parede com blocos solo-cimento e kraftterra. As we know, the separating element is an obstacle to the transition of fire, limiting the spread inside of a building. Knowledge of fire resistance of these elements allows evaluating their performance in a situation of fire. It is important that the separating elements keep their functions during a certain period to allow the evacuation of people and the intervention of firefighters. This dissertation was divided into four parts. The first one focuses on the regulation of fire resistance. In the second part, it is presented the thermal behaviour from some materials and construction products that are used presently. In the third part, it is described three of the fire resistance tests done by LERF, Laboratory of Structures and Fire Resistance of the University of Aveiro. Finally, in the fourth part, it is described one numerical modelling done to a wall of soil-cement and Kraftterra blocks.