University of Porto

Repositório Aberto da Universidade do Porto
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    Um projeto para Vila Nova de Cerveira: O percurso pela construção em madeira

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    A presente dissertação decorre de um conjunto de diferentes momentos e estudos sobre a madeira enquanto material construtivo e impulsionadora do exercício da Arquitetura, realizados ao longo do percurso académico, tanto na Faculdade de Arquitetura da Universidade do Porto (FAUP), como também na École Polytechnique Fédérale de Lausanne (EPFL). Assim, juntamente com o conhecimento adquirido, sobretudo por experimentação e contacto direto com o material, desde o trabalho desenvolvido na unidade curricular de Construção 2, até à vivência intensiva com a madeira durante o semestre de Erasmus no ano letivo 2021/22, cujas experiências foram profusamente esplanadas e analisadas na presente dissertação, alia-se uma investigação sobre a madeira enquanto material construtivo. Esta investigação procura visar diferentes temáticas capazes de criar um entendimento sobre o desenvolvimento da construção em madeira, sobre as propriedades e qualidades da madeira enquanto material construtivo e matéria-prima e sobre métodos de construção que fazem uso de materiais derivados da madeira, como a Glulam e o CLT e quais as suas características e vantagens perante outros materiais e os métodos de construção tradicionais em madeira. É importante de ressalvar que esta investigação acompanha todo o desenvolvimento da dissertação, desde as memórias do percurso académico até ao futuro da Quinta das Laranjeiras. Deste modo, todo o aprendizado teórico e experimental realizado ao longo destes anos académicos resultaram na vontade de realizar um projecto próprio. Assim, através de um exercício prático de projeto, propõe-se adensar a reflexão e o entendimento, não só sobre diferentes técnicas de construção em madeira, como também sobre o domínio sensorial deste material e a sua relação com o utilizador, com a Arquitetura e com a Construção.The present dissertation is the result of a series of different moments and studies about wood as a construction material and as a propelling element for the practice of Architecture, carried out through the whole academic journey, both at the Faculdade de Arquitetura da Universidade do Porto (FAUP), as well as at the École Polytechnique Fédérale de Lausanne (EPFL). Therefore, with the knowledge acquired, mainly through experimentation and direct contact with the material, from the work developed in the Construção 2 curricular unit, to the intensive experience with wood during the Erasmus semester in the 2021/22 academic year, whose experiences were profusely explored and analyzed in this dissertation, it was developed an investigation into wood as a construction material. This research aims to address different themes capable of creating an understanding of the development of wood construction, the properties and qualities of wood as a building material and as a raw product, and the construction methods that make use of materials derived from wood, such as Glulam and CLT, and their characteristics and advantages over other materials and traditional wood construction methods. It is important to emphasize that this research accompanies the entire development of the dissertation, from the memories of the academic journey to the future of Quinta das Laranjeiras. In this way, all the theoretical and experimental learning carried out over the course of these academic years resulted in the desire to create a project of my own. Thus, through a practical design exercise, the aim is to deepen reflection and understanding, not only about different wood construction techniques, but also about the sensory realm of this material and its relationship with the user, with Architecture and with Construction

    Estimates of sensitivity and specificity of serological tests for SARS-CoV-2 specific antibodies using a Bayesian latent class model approach

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    "Objectives: Assessing the accuracy of serological tests for SARS-CoV-2 was challenging due to the lack of a gold standard. This study aimed to estimate the accuracy of SARS-CoV-2-specific serological tests using Bayesian latent class models (BLCM) and compare methods with and without a gold standard. Study design and setting: In this study, we analyzed 356 samples-254 positives, ie, from individuals with a previous SARS-CoV-2 infection diagnosis, and 102 negatives, ie, prepandemic samples-using six different rapid serological tests and one laboratory assay. A BLCM was employed to concurrently estimate the sensitivity and specificity of all serological tests for the immunoglobulin (Ig) M and IgG antibodies specific for SARS-CoV-2. Noninformative priors were used. A sensitivity analysis was conducted considering three methods: 1) reverse transcription-polymerase chain reaction test (RT-PCR) as the gold standard, 2) BLCM with RT-PCR as an imperfect gold standard, and 3) frequentist latent class model (LCM). All analyses used software R version 4.3.0, and BLCM were fitted using package runjags using the software JAGS (Just Another Gibbs Sampler). Results: The BLCM-derived sensitivity for IgM varied from 10.7% [95% credibility interval (CrI):1.9-24.6] to 96.9% (95% CrI: 91.0-100.0), with specificities ranging from 48.3% (95% CrI: 39.0-57.6) to 98.9% (95% CrI: 96.2-100.0). Sensitivity for IgG varied between 76.9% (95% CrI: 68.2-84.7) and 99.1% (95% CrI: 96.1-100.0), and specificity ranged from 49.9% (95% CrI: 19.4-95.8) to 99.3% (95% CrI: 97.2-100.0). LCM results were comparable to BLCM. Considering the RT-PCR as a gold standard underestimated the tests' sensitivity, particularly for IgM. Conclusion: BLCM-derived results deviated from those using a gold standard, which underestimated the tests' characteristics, particularly sensitivity. Although Bayesian and frequentist LCM approaches yielded comparable results, BLCM had the benefit of enabling credibility interval computation even when sample power is limited.

    The effect of the attitude towards risk/ambiguity on examination grades: cross-sectional study in a Portuguese medical school

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    Given the high prevalence of multiple-choice examinations with formula scoring in medical training, several studies have tried to identify other factors in addition to the degree of knowledge of students which influence their response patterns. This study aims to measure the effect of students’ attitude towards risk and ambiguity on their number of correct, wrong, and blank answers. In October 2018, 233 3rd year medical students from the Faculty of Medicine of the University of Porto, in Porto, Portugal, completed a questionnaire which assessed the student’s attitudes towards risk and ambiguity, and aversion to ambiguity in medicine. Simple and multiple regression models and the respective regression coefficients were used to measure the association between the students’ attitudes, and their answers in two examinations that they had taken in June 2018. Having an intermediate level of ambiguity aversion in medicine (as opposed to a very high or low level) was associated with a significant increase in the number of correct answers and decrease in the number of blank answers in the first examination. In the second examination, high levels of ambiguity aversion in medicine were associated with a decrease in the number of wrong answers. Attitude towards risk, tolerance for ambiguity, and gender did not show significant association with the number of correct, wrong, and blank answers for either examination. Students’ ambiguity aversion in medicine is correlated with their performance in multiple-choice examinations with negative marking. Therefore, it is suggested the planning and implementation of counselling sessions with medical students regarding the possible impact of ambiguity aversion on their performance in multiple-choice questions with negative marking.Open access funding provided by FCT|FCCN (b-on). This study did not apply for any funding

    Advice for the update of the EU Menu guidance: results of the ERA EU Menu project

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    The availability of detailed and high-quality food consumption data is essential for EFSA's risk assessments. In 2014, EFSA published the EU Menu guidance on collecting such data in a harmonised way. The ERA EU Menu project aims to give evidence-based recommendations for updating the EU menu guidance. Based on a literature review on the landscape of methods and tools available for national dietary surveys, lessons learned through an evaluation of the data collected under the EU menu, and a symposium on ‘Harmonised Food Consumption Data Collection in Europe: Time to Reflect and Plan Ahead’, recommendations for an update of the EU Menu guidance were derived. Regarding the topic organisation and planning, the current guidance seems adequate. It is recommended to stimulate more data collection on subgroups such as pregnant and lactating women, vegetarians, and adults over 74. For dietary assessment, flexibility is recommended to accommodate differences in the appropriateness of using interviewer-administered or self-administered new –technology-based 24-hour dietary recalls or food records. More specific guidance is recommended regarding the aspects of food description using FoodEx2 facets, standardisation of the food propensity questionnaire, quality monitoring and assurance, data transfer and reporting. Such updated guidance is thought to lead to better data quality and better insight in data quality. Moreover, better harmonised data can be achieved with improvements in various EU Menu guidance aspects. For dietary assessment, creating flexibility is needed due to differences in the degree of digitalisation in European societies and to gain more experience in the large-scale application of self-administered dietary assessment methods. It is recommended that EFSA also uses other strategies to obtain good quality and better harmonised data. These could include financial incentives, tender specifications consistent with the EU Menu guidance, and supporting capacity building and the sharing of protocols, materials, and lessons learned between countries.We highly appreciate all input received from experts in the EFSA Network of Food consumption data, EU Menu survey coordinators to check and complete our information, EFSA colleagues (Sofia Ioannidou, Anastasia Livaniou and Ashraf Khosravi) and collaborators under the tasking grant GP/EFSA/DATA/2021/01 Lot 3 (Androniki Naska, Krystalia Niforou, Elissavet Maria Valanou and Nikolaos Koffas)

    One-year regional brain volume changes as potential predictors of cognitive function in multiple sclerosis: a pilot study

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    BackgroundThe most reliable magnetic resonance imaging (MRI) marker of cognitive dysfunction in multiple sclerosis (MS) is brain atrophy. However, 1-year volumetric changes prior to cognitive assessment were never studied as potential predictors of cognition, which we aim to assess with this pilot work.MethodsTwenty-two MS patients were submitted to a baseline measure of 83 regional brain volumes with MRI and re-evaluated 1 year later; they were also tested with the Brief International Cognitive Assessment for MS (BICAMS): sustained attention and processing speed were examined with the Symbol Digit Modalities Test (SDMT), verbal and visuo-spatial learning and memory with the learning trials from the California Verbal Learning Test-II (CVLT) and the Brief Visuo-spatial Memory Test-revised (BVMT), respectively. Controlling for age, sex, and years of education, a multivariate linear regression model was created for each cognitive score at 1-year follow-up in a backward elimination manner, considering cross-sectional regional volumes and 1-year volume changes as potential predictors.ResultsDecreases in the volumes of the left amygdala and the right lateral orbitofrontal cortex in the year prior to assessment were identified as possible predictors of worse performance in verbal memory (P = 0.009) and visuo-spatial memory (P = 0.001), respectively, independently of cross-sectional brain regional volumes at time of testing.ConclusionOur work reveals novel 1-year regional brain volume changes as potential predictors of cognitive deficits in MS. This suggests a possible role of these regions in such deficits and might contribute to uncover cognitively deteriorating patients, whose detection is still unsatisfying in clinical practice.Open access funding provided by FCT|FCCN (b-on). Biogen, Fundacao para a Ciencia e Tecnologia, UIDB/50026/2020, Fundacao para a ciencia e tecnologia, UIDP/50026/2020, Fundacao para a Ciencia e a Tecnologia, EXPL/MEC-NEU/0888/2021, Torcato Meira

    Highly reconfigurable smart component system

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