11,036 research outputs found

    Anuário científico da Escola Superior de Tecnologia da Saúde de Lisboa - 2021

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    É com grande prazer que apresentamos a mais recente edição (a 11.ª) do Anuário Científico da Escola Superior de Tecnologia da Saúde de Lisboa. Como instituição de ensino superior, temos o compromisso de promover e incentivar a pesquisa científica em todas as áreas do conhecimento que contemplam a nossa missão. Esta publicação tem como objetivo divulgar toda a produção científica desenvolvida pelos Professores, Investigadores, Estudantes e Pessoal não Docente da ESTeSL durante 2021. Este Anuário é, assim, o reflexo do trabalho árduo e dedicado da nossa comunidade, que se empenhou na produção de conteúdo científico de elevada qualidade e partilhada com a Sociedade na forma de livros, capítulos de livros, artigos publicados em revistas nacionais e internacionais, resumos de comunicações orais e pósteres, bem como resultado dos trabalhos de 1º e 2º ciclo. Com isto, o conteúdo desta publicação abrange uma ampla variedade de tópicos, desde temas mais fundamentais até estudos de aplicação prática em contextos específicos de Saúde, refletindo desta forma a pluralidade e diversidade de áreas que definem, e tornam única, a ESTeSL. Acreditamos que a investigação e pesquisa científica é um eixo fundamental para o desenvolvimento da sociedade e é por isso que incentivamos os nossos estudantes a envolverem-se em atividades de pesquisa e prática baseada na evidência desde o início dos seus estudos na ESTeSL. Esta publicação é um exemplo do sucesso desses esforços, sendo a maior de sempre, o que faz com que estejamos muito orgulhosos em partilhar os resultados e descobertas dos nossos investigadores com a comunidade científica e o público em geral. Esperamos que este Anuário inspire e motive outros estudantes, profissionais de saúde, professores e outros colaboradores a continuarem a explorar novas ideias e contribuir para o avanço da ciência e da tecnologia no corpo de conhecimento próprio das áreas que compõe a ESTeSL. Agradecemos a todos os envolvidos na produção deste anuário e desejamos uma leitura inspiradora e agradável.info:eu-repo/semantics/publishedVersio

    Model Diagnostics meets Forecast Evaluation: Goodness-of-Fit, Calibration, and Related Topics

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    Principled forecast evaluation and model diagnostics are vital in fitting probabilistic models and forecasting outcomes of interest. A common principle is that fitted or predicted distributions ought to be calibrated, ideally in the sense that the outcome is indistinguishable from a random draw from the posited distribution. Much of this thesis is centered on calibration properties of various types of forecasts. In the first part of the thesis, a simple algorithm for exact multinomial goodness-of-fit tests is proposed. The algorithm computes exact pp-values based on various test statistics, such as the log-likelihood ratio and Pearson\u27s chi-square. A thorough analysis shows improvement on extant methods. However, the runtime of the algorithm grows exponentially in the number of categories and hence its use is limited. In the second part, a framework rooted in probability theory is developed, which gives rise to hierarchies of calibration, and applies to both predictive distributions and stand-alone point forecasts. Based on a general notion of conditional T-calibration, the thesis introduces population versions of T-reliability diagrams and revisits a score decomposition into measures of miscalibration, discrimination, and uncertainty. Stable and efficient estimators of T-reliability diagrams and score components arise via nonparametric isotonic regression and the pool-adjacent-violators algorithm. For in-sample model diagnostics, a universal coefficient of determination is introduced that nests and reinterprets the classical R2R^2 in least squares regression. In the third part, probabilistic top lists are proposed as a novel type of prediction in classification, which bridges the gap between single-class predictions and predictive distributions. The probabilistic top list functional is elicited by strictly consistent evaluation metrics, based on symmetric proper scoring rules, which admit comparison of various types of predictions

    Evaluation of image quality and reconstruction parameters in recent PET-CT and PET-MR systems

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    In this PhD dissertation, we propose to evaluate the impact of using different PET isotopes for the National Electrical Manufacturers Association (NEMA) tests performance evaluation of the GE Signa integrated PET/MR. The methods were divided into three closely related categories: NEMA performance measurements, system modelling and evaluation of the image quality of the state-of-the-art of clinical PET scanners. NEMA performance measurements for characterizing spatial resolution, sensitivity, image quality, the accuracy of attenuation and scatter corrections, and noise equivalent count rate (NECR) were performed using clinically relevant and commercially available radioisotopes. Then we modelled the GE Signa integrated PET/MR system using a realistic GATE Monte Carlo simulation and validated it with the result of the NEMA measurements (sensitivity and NECR). Next, the effect of the 3T MR field on the positron range was evaluated for F-18, C-11, O-15, N-13, Ga-68 and Rb-82. Finally, to evaluate the image quality of the state-of-the-art clinical PET scanners, a noise reduction study was performed using a Bayesian Penalized-Likelihood reconstruction algorithm on a time-of-flight PET/CT scanner to investigate whether and to what extent noise can be reduced. The outcome of this thesis will allow clinicians to reduce the PET dose which is especially relevant for young patients. Besides, the Monte Carlo simulation platform for PET/MR developed for this thesis will allow physicists and engineers to better understand and design integrated PET/MR systems

    Learning disentangled speech representations

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    A variety of informational factors are contained within the speech signal and a single short recording of speech reveals much more than the spoken words. The best method to extract and represent informational factors from the speech signal ultimately depends on which informational factors are desired and how they will be used. In addition, sometimes methods will capture more than one informational factor at the same time such as speaker identity, spoken content, and speaker prosody. The goal of this dissertation is to explore different ways to deconstruct the speech signal into abstract representations that can be learned and later reused in various speech technology tasks. This task of deconstructing, also known as disentanglement, is a form of distributed representation learning. As a general approach to disentanglement, there are some guiding principles that elaborate what a learned representation should contain as well as how it should function. In particular, learned representations should contain all of the requisite information in a more compact manner, be interpretable, remove nuisance factors of irrelevant information, be useful in downstream tasks, and independent of the task at hand. The learned representations should also be able to answer counter-factual questions. In some cases, learned speech representations can be re-assembled in different ways according to the requirements of downstream applications. For example, in a voice conversion task, the speech content is retained while the speaker identity is changed. And in a content-privacy task, some targeted content may be concealed without affecting how surrounding words sound. While there is no single-best method to disentangle all types of factors, some end-to-end approaches demonstrate a promising degree of generalization to diverse speech tasks. This thesis explores a variety of use-cases for disentangled representations including phone recognition, speaker diarization, linguistic code-switching, voice conversion, and content-based privacy masking. Speech representations can also be utilised for automatically assessing the quality and authenticity of speech, such as automatic MOS ratings or detecting deep fakes. The meaning of the term "disentanglement" is not well defined in previous work, and it has acquired several meanings depending on the domain (e.g. image vs. speech). Sometimes the term "disentanglement" is used interchangeably with the term "factorization". This thesis proposes that disentanglement of speech is distinct, and offers a viewpoint of disentanglement that can be considered both theoretically and practically

    Application of advanced fluorescence microscopy and spectroscopy in live-cell imaging

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    Since its inception, fluorescence microscopy has been a key source of discoveries in cell biology. Advancements in fluorophores, labeling techniques and instrumentation have made fluorescence microscopy a versatile quantitative tool for studying dynamic processes and interactions both in vitro and in live-cells. In this thesis, I apply quantitative fluorescence microscopy techniques in live-cell environments to investigate several biological processes. To study Gag processing in HIV-1 particles, fluorescence lifetime imaging microscopy and single particle tracking are combined to follow nascent HIV-1 virus particles during assembly and release on the plasma membrane of living cells. Proteolytic release of eCFP embedded in the Gag lattice of immature HIV-1 virus particles results in a characteristic increase in its fluorescence lifetime. Gag processing and rearrangement can be detected in individual virus particles using this approach. In another project, a robust method for quantifying Förster resonance energy transfer in live-cells is developed to allow direct comparison of live-cell FRET experiments between laboratories. Finally, I apply image fluctuation spectroscopy to study protein behavior in a variety of cellular environments. Image cross-correlation spectroscopy is used to study the oligomerization of CXCR4, a G-protein coupled receptor on the plasma membrane. With raster image correlation spectroscopy, I measure the diffusion of histones in the nucleoplasm and heterochromatin domains of the nuclei of early mouse embryos. The lower diffusion coefficient of histones in the heterochromatin domain supports the conclusion that heterochromatin forms a liquid phase-separated domain. The wide range of topics covered in this thesis demonstrate that fluorescence microscopy is more than just an imaging tool but also a powerful instrument for the quantification and elucidation of dynamic cellular processes

    TOWARDS AN UNDERSTANDING OF EFFORTFUL FUNDRAISING EXPERIENCES: USING INTERPRETATIVE PHENOMENOLOGICAL ANALYSIS IN FUNDRAISING RESEARCH

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    Physical-activity oriented community fundraising has experienced an exponential growth in popularity over the past 15 years. The aim of this study was to explore the value of effortful fundraising experiences, from the point of view of participants, and explore the impact that these experiences have on people’s lives. This study used an IPA approach to interview 23 individuals, recognising the role of participants as proxy (nonprofessional) fundraisers for charitable organisations, and the unique organisation donor dynamic that this creates. It also bought together relevant psychological theory related to physical activity fundraising experiences (through a narrative literature review) and used primary interview data to substantiate these. Effortful fundraising experiences are examined in detail to understand their significance to participants, and how such experiences influence their connection with a charity or cause. This was done with an idiographic focus at first, before examining convergences and divergences across the sample. This study found that effortful fundraising experiences can have a profound positive impact upon community fundraisers in both the short and the long term. Additionally, it found that these experiences can be opportunities for charitable organisations to create lasting meaningful relationships with participants, and foster mutually beneficial lifetime relationships with them. Further research is needed to test specific psychological theory in this context, including self-esteem theory, self determination theory, and the martyrdom effect (among others)

    Karttatypografia: luettavuuden parantaminen kirjainmuotoilun keinoin topografisissa kartoissa

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    This thesis examines the legibility of type on maps and aims to find out ways to improve it through type design. As type often is an integral part of maps – something that helps the map user navigate, understand, and perceive a wide range of information in an effective way – type design and legibility must be regarded as important design elements. However, even though cartography and typography have extensive theoretical bases, the subject of legibility has not been comprehensively researched in cartographic context. Thus, by combining type design theory and scientific legibility studies with cartographic theory, the legibility of type on maps could be improved. The topic is first studied by an extensive literature review to cover existing concepts and theories of cartography, cartographic typography, and typography. After a competent knowledge basis of these concepts and theories is acquired, the findings are utilised in the design component. The design component is a type family designed specifically to be used with topographic maps: it consists of two elements, a project description that follows the design process of the type family, relating design choices to the theoretical findings and perspectives presented in the literary review, and the finished type family. In conclusion of the design component, several visual studies are made both to compare the design component (type family) to other relevant typefaces, and to validate the possible functionality of the design component in the chosen cartographic application (topographic map). A broad understanding of the topics of the literature review was formed. Cartographic theory observed the overall nature of maps and specified the various map elements and their intended uses. Cartographic typography deepened the understanding of type on maps – it highlighted the specific needs that must be taken into consideration, demonstrated the diversity of typographic situations that might occur, and presented a large set of guidelines to help the mapmaker to achieve better results. Typography and type design focused on the micro-level of type: how the minor design choices affect the whole, and furthermore, through legibility studies, validated certain views and brought new topics into consideration. By combining theoretical literature from these domains, this thesis helped to form a foundation for an improved framework for type de-sign for (topographic) maps. Furthermore, the domains of cartographic typography and typography and type design gave clear suggestions on how the legibility of type on topographic maps can be improved: legibility of type in this context constitutes from multiple components that must be both taken into consideration and be applied to processes of mapmaking and type design.Tässä opinnäytetyössä tutkitaan karttatypografiaa ja pyritään löytämään keinoja parantaa luettavuutta kirjainmuotoilun keinoin. Teksti on usein elimellinen osa karttoja: se helpottaa kartan käyttäjää navigoimaan ja sisäistämään suuren määrän informaatiota tehokkaasti. Siispä kirjainmuotoilua ja luettavuutta tulee pitää tärkeinä karttasuunnittelun työkaluina. Vaikka sekä kartografiassa että typografiassa on olemassa laajat teoreettiset perustat, luettavuutta ei ole kattavasti tutkittu kartografisessa kontekstissa. Yhdistämällä kirjainmuotoilun ja tieteelliset luettavuustutkimukset kartografiseen teoriaan, karttatekstien luettavuutta voidaan parantaa. Aluksi tutustutaan olemassa oleviin konsepteihin ja kartografisiin teorioihin kattavan kirjallisuuskatsauksen avulla. Kun tarpeellinen tietopohja on rakennettu, saavutettua tietämystä hyödynnetään opinnäytetyön projektiosassa, joka tässä tapauksessa on topografisten karttojen yhteydessä käytettävä kirjainperhe. Projektiosio on kaksijakoinen ja pitää sisällään sekä valmiin kirjainperheen, että projektikuvauksen. Projektikuvaus seuraa suunnitteluprosessia ja peilaa tehtyjä valintoja kirjallisuuskatsauksessa esiteltyihin löydöksiin. Projektiosion päätelmässä tutkitaan visuaalisesti kirjainperheen toimintaa ja käyttökelpoisuutta topografisessa karttaympäristössä, sekä verrataan kirjainperheen toimivuutta suhteessa muihin kirjaintyyppeihin. Tutkimuksen perusteella muodostuu laaja ymmärrys aiheesta. Kartografinen teoria valottaa yleisesti karttojen olemusta ja toimintaa, sekä esittelee erilaisia karttalementtejä ja niiden toimintatapoja. Karttatypografian teoria syventää ymmärrystä tekstin käyttäytymisestä karttaympäristössä, esittelee karttatypografian erityispiirteitä, ja tarjoaa laajan karttatypografisen ohjeiston. Typografian ja kirjainmuotoilun teoria keskittyy mikrotason aiheisiin: kuinka vähäpätöisiltä vaikuttavat suunnitteluvalinnat vaikuttavat kokonaisuuteen, ja kuinka luettavuustutkimukset auttavat näkemään asioita uudessa valossa. Tämä opinnäytetyö auttaa parantamaan kirjainmuotoilua (topografisessa) karttaympäristössä yhdistämällä edellä mainittujen alojen teorioita keskenään ja pohjustamalla paranneltuja suunniteluvalintoja. Yhdistetty teoria viittaa selkeästi siihen, että luettavuus karttaympäristössä koostuu lukuisista osatekijöistä – nämä osatekijät tulee ymmärtää, ottaa huomioon, ja soveltaa sekä karttojen että niille suunniteltujen kirjaintyyppien suunnitteluprosesseissa

    A Non-intrusive Approach for Physics-constrained Learning with Application to Fuel Cell Modeling

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    A data-driven model augmentation framework, referred to as Weakly-coupled Integrated Inference and Machine Learning (IIML), is presented to improve the predictive accuracy of physical models. In contrast to parameter calibration, this work seeks corrections to the structure of the model by a) inferring augmentation fields that are consistent with the underlying model, and b) transforming these fields into corrective model forms. The proposed approach couples the inference and learning steps in a weak sense via an alternating optimization approach. This coupling ensures that the augmentation fields remain learnable and maintain consistent functional relationships with local modeled quantities across the training dataset. An iterative solution procedure is presented in this paper, removing the need to embed the augmentation function during the inference process. This framework is used to infer an augmentation introduced within a Polymer electrolyte membrane fuel cell (PEMFC) model using a small amount of training data (from only 14 training cases.) These training cases belong to a dataset consisting of high-fidelity simulation data obtained from a high-fidelity model of a first generation Toyota Mirai. All cases in this dataset are characterized by different inflow and outflow conditions on the same geometry. When tested on 1224 different configurations, the inferred augmentation significantly improves the predictive accuracy for a wide range of physical conditions. Predictions and available data for the current density distribution are also compared to demonstrate the predictive capability of the model for quantities of interest which were not involved in the inference process. The results demonstrate that the weakly-coupled IIML framework offers sophisticated and robust model augmentation capabilities without requiring extensive changes to the numerical solver

    Chinese Benteng Women’s Participation in Local Development Affairs in Indonesia: Appropriate means for struggle and a pathway to claim citizen’ right?

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    It had been more than two decades passing by aftermath the devastating Asia’s Financial Crisis in 1997, subsequently followed by Suharto’s step down from his presidential throne which he occupied for more than three decades. The financial turmoil turned to a political disaster furthermore has led to massive looting that severely impacted Indonesians of Chinese descendant, including unresolved mystery of the most atrocious sexual violation against women and covert killings of students and democracy activists in this country. Since then, precisely aftermath May 1998, which publicly known as “Reformasi”1, Indonesia underwent political reform that eventually corresponded positively to its macroeconomic growth. Twenty years later, in 2018, Indonesia captured worldwide attention because it has successfully hosted two internationally renowned events, namely the Asian Games 2018 – the most prestigious sport events in Asia – conducted in Jakarta and Palembang; and the IMF/World Bank Annual Meeting 2018 in Bali. Particularly in the IMF/World Bank Annual Meeting, this event has significantly elevated Indonesia’s credibility and international prestige in the global economic powerplay as one of the nations with promising growth and openness. However, the narrative about poverty and inequality, including increasing racial tension, religious conservatism, and sexual violation against women are superseded by friendly climate for foreign investment and eventually excessive glorification of the nation’s economic growth. By portraying the image of promising new economic power, as rhetorically promised by President Joko Widodo during his presidential terms, Indonesia has swept the growing inequality in this highly stratified society that historically compounded with religious and racial tension under the carpet of digital economy.Arte y Humanidade
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