Database repairs with answer set programming

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

Smart Plastic Antibody Material (SPAM) tailored on disposable screen printed electrodes for protein recognition: application to Myoglobin detection

This work introduces two major changes to the conventional protocol for designing plastic antibodies: (i) the imprinted sites were created with charged monomers while the surrounding environment was tailored using neutral material; and (ii) the protein was removed from its imprinted site by means of a protease, aiming at preserving the polymeric network of the plastic antibody. To our knowledge, these approaches were never presented before and the resulting material was named here as smart plastic antibody material (SPAM). As proof of concept, SPAM was tailored on top of disposable gold-screen printed electrodes (Au-SPE), following a bottom-up approach, for targeting myoglobin (Myo) in a point-of-care context. The existence of imprinted sites was checked by comparing a SPAM modified surface to a negative control, consisting of similar material where the template was omitted from the procedure and called non-imprinted materials (NIMs). All stages of the creation of the SPAM and NIM on the Au layer were followed by both electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). AFM imaging was also performed to characterize the topography of the surface. There are two major reasons supporting the fact that plastic antibodies were effectively designed by the above approach: (i) they were visualized for the first time by AFM, being present only in the SPAM network; and (ii) only the SPAM material was able to rebind to the target protein and produce a linear electrical response against EIS and square wave voltammetry (SWV) assays, with NIMs showing a similar-to-random behavior. The SPAM/Au-SPE devices displayed linear responses to Myo in EIS and SWV assays down to 3.5 μg/mL and 0.58 μg/mL, respectively, with detection limits of 1.5 and 0.28 μg/mL. SPAM materials also showed negligible interference from troponin T (TnT), bovine serum albumin (BSA) and urea under SWV assays, showing promising results for point-of-care applications when applied to spiked biological fluids.

Carnitine tailored Sensors on Surface Molecular Imprinting based on Graphene layers

III Jornadas de Electroquímica e Inovação (Electroquímica e Nanomateriais), na Universidade de Trás-os-Montes e Alto Douro, Vila Real, 16 a 17 de Setembro de 2013

Host-Tailored Sensors for Carnitine Potentiometric Measurements based on Surface Molecular Imprinting

Graduate Student Symposium on Molecular Imprinting 2013, na Queen’s University, Belfast, United Kingdom, 15 a 17 de Agosto de 2013

Parallel Software framework for time-critical many-core systems

The recent technological advancements and market trends are causing an interesting phenomenon towards the convergence of High-Performance Computing (HPC) and Embedded Computing (EC) domains. On one side, new kinds of HPC applications are being required by markets needing huge amounts of information to be processed within a bounded amount of time. On the other side, EC systems are increasingly concerned with providing higher performance in real-time, challenging the performance capabilities of current architectures. The advent of next-generation many-core embedded platforms has the chance of intercepting this converging need for predictable high-performance, allowing HPC and EC applications to be executed on efficient and powerful heterogeneous architectures integrating general-purpose processors with many-core computing fabrics. To this end, it is of paramount importance to develop new techniques for exploiting the massively parallel computation capabilities of such platforms in a predictable way. P-SOCRATES will tackle this important challenge by merging leading research groups from the HPC and EC communities. The time-criticality and parallelisation challenges common to both areas will be addressed by proposing an integrated framework for executing workload-intensive applications with real-time requirements on top of next-generation commercial-off-the-shelf (COTS) platforms based on many-core accelerated architectures. The project will investigate new HPC techniques that fulfil real-time requirements. The main sources of indeterminism will be identified, proposing efficient mapping and scheduling algorithms, along with the associated timing and schedulability analysis, to guarantee the real-time and performance requirements of the applications.

Sintomas somatoformes em Medicina Geral e Familiar

RESUMO: Os doentes que vão à consulta com sintomas físicos para os quais o médico não encontra uma causa orgânica, são frequentes na Medicina Geral e Familiar, embora não sejam específicos, e são o objecto de estudo do presente trabalho. Não deixar uma doença por diagnosticar (erro de tipo II) sem contudo rotular pessoas saudáveis como doentes (erro de tipo I) é um dos mais difíceis problemas da prática clínica diária e para o qual não existe uma orientação infalível e não é previsível que alguma vez venha a existir. Mas se o diagnóstico de doença ou não-doença é difícil, o tratamento dos que não tem doença, embora com sofrimento, também não é mais fácil, sobretudo, se estivermos conscientes do sofrimento que determina a medicalização e a iatrogenia. O presente trabalho está estruturado em 3 partes. Na primeira parte descrevemos a nossa visão integrada do que apreendemos da leitura da literatura publicada e à qual tivemos acesso. À semelhança do que se verifica na maioria das áreas da Medicina esta é também uma em que o conhecimento cresce a ritmo exponencial. No entanto, à falta de conceitos precisos e de definições consensuais sucede um conhecimento, por vezes, pouco consistente, tanto mais que estamos na fronteira entre a cultura leiga e a cultura erudita médica em que os significados devem, a todo o momento, ser validados. Fizemos uma revisão sobre as definições do que está em questão, sobre o que se sabe sobre a frequência dos sintomas físicos na população, quantos recorrem aos serviços de saúde e o que lhes é feito. Passámos por uma revisão da fisiologia destes sintomas e algumas explicações fisiopatológicas para terminarmos sobre o que os doentes pensam sobre os seus sintomas e os cuidados que recebem e o que os profissionais pensam sobre estes doentes. Esta parte termina com uma revisão das propostas de abordagem para este tipo de doentes. Na segunda parte, descrevemos os estudos empíricos focados no problema dos pacientes com sintomas físicos mas sem evidência de doença orgânica. Começa por uma apresentação dos aspectos processuais e metodológicos dos estudos realizados, mais especificamente, de dois estudos quantitativos e um qualitativo. No primeiro estudo pretendeu-se avaliar quais são os sintomas físicos e a sua frequência na população em geral e a frequência de pacientes que procuram (ou não) os serviços de saúde tendo como motivo este tipo de sintomas. O objectivo deste estudo é contribuir para a demonstração que este tipo de sintomas faz parte da vida do dia-a-dia e que, na maioria das vezes, só por si não significa doença, sem contudo negar que representa sofrimento, por vezes até maior do que quando há patologia orgânica. Se no primeiro estudo era demonstrar que os sintomas físicos são frequentes na população, no segundo estudo o objectivo é demonstrar que pacientes com este tipo de sintomas são igualmente frequentes e que o tipo de sintomas apresentados na consulta não difere dos referidos pela população em geral. Pretendia-se ainda saber o que é feito ou proposto pelo médico a estes doentes e se estes doentes traziam ou não, junto com os sintomas, ideias explicativas para os mesmos. Finalmente e não menos importante, é avaliar o grau de fidedignidade do diagnóstico de sintoma somatoforme, chamando assim ao sintoma físico que foi “levado” à consulta e que o médico diagnosticou como não tendo causa orgânica. O terceiro estudo parte do conhecimento adquirido que a Medicina tem muitas respostas para este problema, mas poucas que se possam considerar satisfatórias se usadas isoladamente. Que a maioria das soluções é procurada entre a cultura médica e num paradigma reducionista de separação mente-corpo. Contudo, se o sintoma é “construído” pelo doente, se o principal problema não está no sintoma mas na forma como o paciente o vê, então pareceu-nos lógico que a solução também tem que passar por integrarmos no plano de abordagem o que o doente entende ser melhor para si. Nesta sequência, entrevistaram-se alguns doentes cujo diagnóstico de sintomas somatoformes estava demonstrado pelo teste do tempo. Por isso, entrevistaram-se doentes que já tinham ido à consulta de MGF há mais de 6 meses por sintomas somatoformes e, na data da entrevista, o diagnóstico se mantinha inalterado, independentemente da sua evolução. As entrevistas visaram conhecer as ideias dos doentes sobre o que as motivou a procurarem a consulta, o que pensavam da forma como foram cuidados e que ideias tinham sobre o que os profissionais de saúde devem fazer para os ajudar a restabelecer o equilíbrio com o seu ambiente evitando a medicalização, a iatrogenia e a evolução para a cronicidade. Na terceira parte, discutem-se e integram-se os resultados encontrados no conhecimento previamente existente. Tenta-se teorizar, fazer doutrina sobre o tema e contribuir para abordagens terapêuticas mais personalizadas, abrangentes, variadas e multimodais, baseadas sempre no método clínico centrado no paciente, ou de modo menos correcto mas enfático, baseadas no método centrado na relação. Apresentam-se algumas hipóteses de trabalhos futuros sobre o tema e, sobretudo, esperamos ter contribuído para o reconhecimento da necessidade de a comunicação médico-doente ser uma aprendizagem transversal a todos os profissionais de saúde e ao longo da vida, com a ideia que é sempre possível fazer melhor, caso contrário tenderemos, inexoravelmente, a fazer cada vez pior.-----------ABSTRACT: Patients who go to consultation with physical symptoms, for which the doctor does not find an organic cause, are the subject of the present study. They are common in family medicine, although not specific. Do not let an undiagnosed disease (type II error), but without labeling healthy people as patients with disease (type I error) is one of the most difficult problems in clinical practice and for which doesn’t exist an infallible guide and it is unlikely that any since coming into existence. But, if the diagnosis of disease or non-disease is difficult, the treatment of those who do not have the disease, though suffering, it is not easy, especially if we are aware of the suffering that medicalization and iatrogenic determines. This work is structured in three parts. In the first part we describe our integrated view of what we grasp from reading the published literature and to which we had access. Similar to that found in most areas of medicine, this is also one in which knowledge grows exponentially. However, the absence of precise concepts and consensual definitions determines an inconsistent knowledge, especially because we're on the border between secular culture and medical culture where, at all times, the meaning must be validated. We did a review on the definitions of what is at issue, what is known about the frequency of physical symptoms in the population, how many use the services of health and what they receive as care. We went through a review of the physiology of these symptoms and some pathophysiological explanations, to finish on what patients think about their symptoms and how they perceived the care they received and, finally, what professionals think about these patients. This part ends with a review of the approaches proposed for such patients. In the second part, we describe the empirical studies focused on the problem of patients with physical symptoms but no evidence of organic disease. Begins with a presentation of the procedural and methodological aspects of studies, more specifically, two quantitative and one qualitative. The first study sought to assess which are the physical symptoms, their incidence in the general population and the frequency they seek (or not) health services on behalf of those symptoms. The aim behind this study was to contribute to the demonstration that this type of symptoms is part of life's day-to-day and that, in most cases, does not represent disease by itself, without denying that they represent suffering, sometimes even greater than when there are organic disease. The first study endeavor to demonstrate that the physical symptoms are common in the population. The second study aspires to demonstrate that patients with such symptoms are also common and that the type of symptoms presented in the consultation does not differ from those in the general population. The aim was also to know what is done or proposed by the physician for these patients and if these patients brought or not, along with the symptoms, explanatory ideas for them. Finally and not least, it would try to assess the degree of reliability of diagnosis of somatoform symptoms, thus drawing the physical symptom that patient presents in the consultation and that the doctor diagnosed as having no organic cause. The third study starts from the acquired knowledge that medicine has many answers to this problem, but few can be considered satisfactory if used in isolation. The most solutions are sought in the medical culture and based on a reductionist paradigm of mind-body. However, if the symptom is "built" by the patient, if the main problem is not the symptom but the way the patient sees it, then it seemed logical to us that the solution must integrate the approaches that patients believes are best for them. Subsequently, a few patients, whose diagnosis of somatoform symptoms was demonstrated by the test of time, were interviewed. Therefore, patients who were interviewed had gone to the consultation of family medicine more than 6 months before for somatoform symptoms and. at the moment of the interview, the diagnosis remained unchanged, regardless of their evolution. The interviews aimed to ascertain the patients' ideas about what motivated them to seek consultation, what they thought about the care they got and which ideas they have about what health professionals should do to help these patients to re-establish equilibrium with its environment avoiding medicalization, iatrogenic effects and the evolution to chronicity. In the third section, we discuss and integrate the results found in previously existing knowledge. Attempts to theorize on the subject and contribute to more personalized treatment, comprehensive, varied and multi-modal approaches, always based on patient-centered clinical method, with emphasis on the relationship. We presents some hypotheses for future work on the subject and,above all, defend the recognition of the importance of lifelong learning communication skills for all health professionals, with the idea that we can always do better, otherwise we tend inexorably to do worse.

Machine ethics via logic programming

Machine ethics is an interdisciplinary field of inquiry that emerges from the need of imbuing autonomous agents with the capacity of moral decision-making. While some approaches provide implementations in Logic Programming (LP) systems, they have not exploited LP-based reasoning features that appear essential for moral reasoning. This PhD thesis aims at investigating further the appropriateness of LP, notably a combination of LP-based reasoning features, including techniques available in LP systems, to machine ethics. Moral facets, as studied in moral philosophy and psychology, that are amenable to computational modeling are identified, and mapped to appropriate LP concepts for representing and reasoning about them. The main contributions of the thesis are twofold. First, novel approaches are proposed for employing tabling in contextual abduction and updating – individually and combined – plus a LP approach of counterfactual reasoning; the latter being implemented on top of the aforementioned combined abduction and updating technique with tabling. They are all important to model various issues of the aforementioned moral facets. Second, a variety of LP-based reasoning features are applied to model the identified moral facets, through moral examples taken off-the-shelf from the morality literature. These applications include: (1) Modeling moral permissibility according to the Doctrines of Double Effect (DDE) and Triple Effect (DTE), demonstrating deontological and utilitarian judgments via integrity constraints (in abduction) and preferences over abductive scenarios; (2) Modeling moral reasoning under uncertainty of actions, via abduction and probabilistic LP; (3) Modeling moral updating (that allows other – possibly overriding – moral rules to be adopted by an agent, on top of those it currently follows) via the integration of tabling in contextual abduction and updating; and (4) Modeling moral permissibility and its justification via counterfactuals, where counterfactuals are used for formulating DDE.

Augmenting spaces and creating interactive experiences using video camera networks

This research addresses the problem of creating interactive experiences to encourage people to explore spaces. Besides the obvious spaces to visit, such as museums or art galleries, spaces that people visit can be, for example, a supermarket or a restaurant. As technology evolves, people become more demanding in the way they use it and expect better forms of interaction with the space that surrounds them. Interaction with the space allows information to be transmitted to the visitors in a friendly way, leading visitors to explore it and gain knowledge. Systems to provide better experiences while exploring spaces demand hardware and software that is not in the reach of every space owner either because of the cost or inconvenience of the installation, that can damage artefacts or the space environment. We propose a system adaptable to the spaces, that uses a video camera network and a wi-fi network present at the space (or that can be installed) to provide means to support interactive experiences using the visitor’s mobile device. The system is composed of an infrastructure (called vuSpot), a language grammar used to describe interactions at a space (called XploreDescription), a visual tool used to design interactive experiences (called XploreBuilder) and a tool used to create interactive experiences (called urSpace). By using XploreBuilder, a tool built of top of vuSpot, a user with little or no experience in programming can define a space and design interactive experiences. This tool generates a description of the space and of the interactions at that space (that complies with the XploreDescription grammar). These descriptions can be given to urSpace, another tool built of top of vuSpot, that creates the interactive experience application. With this system we explore new forms of interaction and use mobile devices and pico projectors to deliver additional information to the users leading to the creation of interactive experiences. The several components are presented as well as the results of the respective user tests, which were positive. The design and implementation becomes cheaper, faster, more flexible and, since it does not depend on the knowledge of a programming language, accessible for the general public.

Machine diagnosis based on artificial immune systems

Nowadays, many of the manufactory and industrial system has a diagnosis system on top of it, responsible for ensuring the lifetime of the system itself. It achieves this by performing both diagnosis and error recovery procedures in real production time, on each of the individual parts of the system. There are many paradigms currently being used for diagnosis. However, they still fail to answer all the requirements imposed by the enterprises making it necessary for a different approach to take place. This happens mostly on the error recovery paradigms since the great diversity that is nowadays present in the industrial environment makes it highly unlikely for every single error to be fixed under a real time, no production stop, perspective. This work proposes a still relatively unknown paradigm to manufactory. The Artificial Immune Systems (AIS), which relies on bio-inspired algorithms, comes as a valid alternative to the ones currently being used. The proposed work is a multi-agent architecture that establishes the Artificial Immune Systems, based on bio-inspired algorithms. The main goal of this architecture is to solve for a resolution to the error currently detected by the system. The proposed architecture was tested using two different simulation environment, each meant to prove different points of views, using different tests. These tests will determine if, as the research suggests, this paradigm is a promising alternative for the industrial environment. It will also define what should be done to improve the current architecture and if it should be applied in a decentralised system.

An equity wealth preservation strategy: Following the macro trend

Financial crisis have happened in the past and will continue to do so in the future. In the most recent 2008 crisis, global equities (as measured by the MSCI ACWI index) lost a staggering 54.2% in USD, on the year. During those periods wealth preservation becomes at the top of most investor’s concerns. The purpose of this paper is to develop a strategy that protects the investment during bear markets and significant market corrections, generates capital appreciation, and that can support Millennium BCP’s Wealth Management Unit on their asset allocation procedures. This strategy extends the Dual Momentum approach introduced by Gary Antonacci (2014) in two ways. First, the investable set of securities in the equities space increases from two to four. Besides the US it will comprise the Japanese, European (excl. UK) and EM equity indices. Secondly, it adds a volatility filter as well as three indicators related to the business cycle and the state of the economy, which are relevant to decide on the strategy’s exposure to equities. Overall the results attest the resiliency of the strategy before, during and after historical financial crashes, as it drastically reduces the downside exposure and consistently outperforms the benchmark index by providing higher mean returns with lower variance.

Maternal attachment representations in relation to emotional availability and discipline behaviour

"Published online: 15 Sep 2015."

Graphene-based nanostructures: Plasmonics in the THz range

The properties of surface plasmon-polaritons (SPPs) in graphene are discussed and several possible ways of coupling electromagnetic radiation in the terahertz (THz) spectral range to this type of surface waves are described: (i) the attenuated total reflection (ATR) method employing a prism, (ii) graphene-based gratings or graphene monolayers with modulated conductivity, (iii) a metal stripe on top of the graphene layer, and (iv) a nanoparticle located above it. Potentially interesting for applications SPP effects, such as switching, modulation and polarization of THz radiation, as well as its enhanced absorption in graphene, are considered. The discussion also concerns the impact of the nonlinear properties of graphene, such as optical bistability.

Multithreading RTOS processor design

Tese de Doutoramento Plano Doutoral em Engenharia Eletrónica e de Computadores.

Patterned CNT-PDMS nanocomposites for flexible pressure sensors

This paper reports the fabrication process and characterization of a flexible pressure sensor based on polydimethylsiloxane (PDMS) and multi-walled carbon nanotubes (CNT-PDMS). The proposed approach relies on patterned CNT-PDMS nanocomposite strain gauges fabricated with SU-8 microstructures (with the micropatterns) in a low‑cost and simple fabrication process. This nanocomposite polymer is mounted over a PDMS membrane, which, in turn, lies on top of a PDMS diaphragm like structure. This configuration enables the PDMS membrane to bend when pressure is applied, thereby affecting the nanocomposite strain gauges, effectively changing their electrical resistance. Carbon nanotubes have several advantages such as excellent mechanical properties, high electrical conductivity and thermal stability. Furthermore, the measurement range of the proposed sensor can be adapted according to the application by varying the CNTs content and geometry of microstructure. In addition, the sensor’s biocompatibility, low cost and simple fabrication makes it very appealing for biomechanical strain sensing. The sensor’s sensitivity was about 0.073%ΔR/mmHg.

Flexible gastrointestinal motility pressure sensors based on aluminum thin-film strain-gauge arrays

This paper reports on an innovative approach to measuring intraluminal pressure in the upper gastrointestinal (GI) tract, especially monitoring GI motility and peristaltic movements. The proposed approach relies on thin-film aluminum strain gauges deposited on top of a Kapton membrane, which in turn lies on top of an SU-8 diaphragm-like structure. This structure enables the Kapton membrane to bend when pressure is applied, thereby affecting the strain gauges and effectively changing their electrical resistance. The sensor, with an area of 3.4 mm2, is fabricated using photolithography and standard microfabrication techniques (wet etching). It features a linear response (R2 = 0.9987) and an overall sensitivity of 2.6 mV mmHg−1. Additionally, its topology allows a high integration capability. The strain gauges’ responses to pressure were studied and the fabrication process optimized to achieve high sensitivity, linearity, and reproducibility. The sequential acquisition of the different signals is carried out by a microcontroller, with a 10-bit ADC and a sample rate of 250 Hz. The pressure signals are then presented in a user-friendly interface, developed using the Integrated Development Environment software, QtCreator IDE, for better visualization by physicians.