959 resultados para mental computation strategies


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RESUMO: A saúde mental é influenciada pelos comportamentos tanto como estes são influenciados pela saúde mental. Por isso é importante compreender quer a saúde mental quer os comportamentos adoptados pelo indivíduo em qualquer momento do seu ciclo vital para melhor poder actuar quando e sempre que necessário. Nos estudantes universitários, não sendo uma população de risco, a saúde mental e os comportamentos de risco afectam não só o próprio estudante e quem com ele convive mas também as próprias instituições que o acolhem. O presente estudo teve como objectivos: nos estudantes universitários 1) caracterizar a saúde mental global; 2) caracterizar os níveis de sintomatologia depressiva e ansiosa; 3) identificar os padrões de comportamentos de risco; 4) analisar a relação entre saúde mental global, depressão, ansiedade e comportamentos de risco. Para tal realizou-se um estudo quantitativo, descritivo, correlacional, transversal e exploratório com 1968 estudantes do 1º ciclo da Universidade da Beira Interior e dos Institutos Politécnicos da Guarda, Castelo Branco e Portalegre. Foram utilizados como instrumentos de investigação uma ficha de Caracterização Socio-Demográfica; o Mental Health Inventory-5; o Patient Health Questionnaire-9; Generalized Anxiety Disorder-7; e o Questionário de Comportamentos de Risco em Estudantes Universitários. Os principais resultados mostraram que 18,3% (n=360) apresentavam saúde mental negativa; 17,7% sintomatologia depressiva moderada a severa; 15,6% sintomatologia ansiosa moderada a severa; e que apenas 15% dos que apresentavam saúde mental global negativa recorreu a ajuda profissional. As mulheres, os alunos de 1ª e 4º ano, e os alunos dos cursos de Artes e Letras apresentavam níveis de saúde mental global inferiores. O Consumo de álcool foi superior nos homens, nos estudantes das áreas de Ciências e Ciências da Saúde e nos estudantes deslocados. Os estudantes com mais de 3 unidades curriculares em atraso apresentavam maior sintomatologia depressiva e ansiosa. Os resultados mostraram ainda que quanto mais positiva a saúde mental global maior o consumo de bebidas alcoólicas e menor a sintomatologia depressiva e ansiosa. As variáveis Curso e Sexo influenciam significativamente a saúde mental global, a depressão e a ansiedade. Apesar de a maioria dos estudantes inquiridos não revelar problemas de saúde mental nem apresentar comportamentos de risco, as principais conclusões apontam para a necessidade de programas de educação para a saúde assim como de programas de literacia de saúde mental para as instituições poderem identificar precocemente as situações problemáticas e ajudar os próprios estudantes a reconhecer em si o sofrimento psicológico e a necessidade de procurar apoio profissional.---------------------------------- ABSTRACT: Mental health is influenced by behaviours as much as behaviours are influenced by mental health. Thus, it is important to understand not only the mental health but also the behaviours adopted by an individual at any stage of its vital cycle in order to accurately intervene whenever and always deemed necessary. Regarding college students, despite not being deemed as a population at risk, mental health and risk behaviours affect not only the student itself and whoever interacts with him but also the institutions that host them. The main purposes of this study were regarding college students 1) characterize the overall mental health; 2) characterize the levels of depression and anxiety symptoms; 3) identify the risk behaviours patterns; and 4) analyse the relation between overall mental health, depression, anxiety and risk behaviours. With that scope a quantitative, descriptive, correlated, transversal and exploratory study has been conducted with 1968 students of the 1st cycle of the University of Beira Interior and of the Polytechnic Institutions of Guarda, Castelo Branco and Portalegre. The investigation instruments used were a chart of Socio-Demographic Characterization; the Mental Health Inventory-5; the Patient Health Questionnaire-9; the Generalized Anxiety Disorder-7; and one Questionnaire of Risk Behaviours in College Students. The main results showed that 18.3% (n=360) revealed negative mental health; 17.7% moderated to severe depression symptoms; 15.6% moderated to severe anxiety symptoms; and that only 15% of those revealing negative overall mental health have seek for professional help. Females, students of the 1st and 4th years and students of the Artes and Letras courses revealed inferior levels of overall mental health. Alcohol consumption is higher in males, in the Sciences and Health Sciences’ students and on displaced students. Students with more than 3 curricular units in delay revealed higher depression and anxiety symptoms. The results also showed that the more positive overall mental health the higher alcohol consumption and the lower depression and anxiety symptoms. The Course and Sex variations significantly influence the overall mental health, the depression and the anxiety. Although the majority of the enquired students did not reveal mental health issues or present risk behaviours, the main conclusions indicate the need to implement health education and mental health literacy programmes in order to enable the institutions to prematurely identify problematic situations and help students to recognize the psychological suffering and the need to seek for professional help.

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The impact of microbial activity on the deterioration of cultural heritage is a well-recognized global problem. Glazed wall tiles constitute an important part of the worldwide cultural heritage. When exposed outdoors, biological colonization and consequently biodeterioration may occur. Few studies have dealt with this issue, as shown in the literature review on biodiversity, biodeterioration and bioreceptivity of architectural ceramic materials. Due to the lack of knowledge on the biodeteriogens affecting these assets, the characterization of microbial communities growing on Portuguese majolica glazed tiles, from Pena National Palace (Sintra, Portugal) and another from Casa da Pesca (Oeiras, Portugal) was carried out by culture and molecular biology techniques. Microbial communities were composed of microalgae, cyanobacteria, bacteria and fungi, including a new fungal species (Devriesia imbrexigena) described for the first time. Laboratory-based colonization experiments were performed to assess the biodeterioration patterns and bioreceptivity of glazed wall tiles produced in laboratory. Microorganisms previously identified on glazed tiles were inoculated on pristine and artificially aged tile models and incubated under laboratory conditions for 12 months. Phototrophic microorganisms were able to grow into glaze fissures and the tested fungus was able to form oxalates over the glaze. The bioreceptivity of artificially aged tiles was higher for phototrophic microorganisms than pristine tile models. A preliminary approach on mitigation strategies based on in situ application of commercial biocides and titanium dioxide (TiO2) nanoparticles on glazed tiles demonstrated that commercial biocides did not provide long term protection. In contrast, TiO2 treatment caused biofilm detachment. In addition, the use of TiO2 thin films on glazed wall tiles as a protective coating to prevent biological colonization was analysed under laboratorial conditions. Finally, conservation notes on tiles exposed to biological colonization were presented.

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Dissertação de Mestrado apresentada ao ISPA - Instituto Universitário

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Economics is a social science which, therefore, focuses on people and on the decisions they make, be it in an individual context, or in group situations. It studies human choices, in face of needs to be fulfilled, and a limited amount of resources to fulfill them. For a long time, there was a convergence between the normative and positive views of human behavior, in that the ideal and predicted decisions of agents in economic models were entangled in one single concept. That is, it was assumed that the best that could be done in each situation was exactly the choice that would prevail. Or, at least, that the facts that economics needed to explain could be understood in the light of models in which individual agents act as if they are able to make ideal decisions. However, in the last decades, the complexity of the environment in which economic decisions are made and the limits on the ability of agents to deal with it have been recognized, and incorporated into models of decision making in what came to be known as the bounded rationality paradigm. This was triggered by the incapacity of the unboundedly rationality paradigm to explain observed phenomena and behavior. This thesis contributes to the literature in three different ways. Chapter 1 is a survey on bounded rationality, which gathers and organizes the contributions to the field since Simon (1955) first recognized the necessity to account for the limits on human rationality. The focus of the survey is on theoretical work rather than the experimental literature which presents evidence of actual behavior that differs from what classic rationality predicts. The general framework is as follows. Given a set of exogenous variables, the economic agent needs to choose an element from the choice set that is avail- able to him, in order to optimize the expected value of an objective function (assuming his preferences are representable by such a function). If this problem is too complex for the agent to deal with, one or more of its elements is simplified. Each bounded rationality theory is categorized according to the most relevant element it simplifes. Chapter 2 proposes a novel theory of bounded rationality. Much in the same fashion as Conlisk (1980) and Gabaix (2014), we assume that thinking is costly in the sense that agents have to pay a cost for performing mental operations. In our model, if they choose not to think, such cost is avoided, but they are left with a single alternative, labeled the default choice. We exemplify the idea with a very simple model of consumer choice and identify the concept of isofin curves, i.e., sets of default choices which generate the same utility net of thinking cost. Then, we apply the idea to a linear symmetric Cournot duopoly, in which the default choice can be interpreted as the most natural quantity to be produced in the market. We find that, as the thinking cost increases, the number of firms thinking in equilibrium decreases. More interestingly, for intermediate levels of thinking cost, an equilibrium in which one of the firms chooses the default quantity and the other best responds to it exists, generating asymmetric choices in a symmetric model. Our model is able to explain well-known regularities identified in the Cournot experimental literature, such as the adoption of different strategies by players (Huck et al. , 1999), the inter temporal rigidity of choices (Bosch-Dom enech & Vriend, 2003) and the dispersion of quantities in the context of di cult decision making (Bosch-Dom enech & Vriend, 2003). Chapter 3 applies a model of bounded rationality in a game-theoretic set- ting to the well-known turnout paradox in large elections, pivotal probabilities vanish very quickly and no one should vote, in sharp contrast with the ob- served high levels of turnout. Inspired by the concept of rhizomatic thinking, introduced by Bravo-Furtado & Côrte-Real (2009a), we assume that each per- son is self-delusional in the sense that, when making a decision, she believes that a fraction of the people who support the same party decides alike, even if no communication is established between them. This kind of belief simplifies the decision of the agent, as it reduces the number of players he believes to be playing against { it is thus a bounded rationality approach. Studying a two-party first-past-the-post election with a continuum of self-delusional agents, we show that the turnout rate is positive in all the possible equilibria, and that it can be as high as 100%. The game displays multiple equilibria, at least one of which entails a victory of the bigger party. The smaller one may also win, provided its relative size is not too small; more self-delusional voters in the minority party decreases this threshold size. Our model is able to explain some empirical facts, such as the possibility that a close election leads to low turnout (Geys, 2006), a lower margin of victory when turnout is higher (Geys, 2006) and high turnout rates favoring the minority (Bernhagen & Marsh, 1997).

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Mental health awareness has been rising worldwide, motivated by its social and economic costs. Despite the investment in research in neuroscience in the recent years, little is known about the underlying mechanisms in the brain that are correlated with psychiatric conditions. This project, through two feature articles suitable to be published in magazines, provides perspectives onto mental health research. First it presents an example where psychiatry joins forces with neuroscience and computer science in an interdisciplinary effort to improve the life of those affected by mental disorders. The second article gathers opinions which claim that mental health research priorities should be set by patients themselves, or even that people with lived experience of mental health issues should have an active role in that research. This project was planned and researched while I was an Erasmus student at Nottingham Trent University, in the United Kingdom.

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AbstractINTRODUCTION: The use of the Self-Image Form (SIF) expands the identification of active leprosy cases to neighbors of index cases.METHODS: The SIF was used to screen two groups: case (neighbors of index cases of leprosy) and control (individuals residing next to houses without leprosy) group. A specialist investigated suspected leprosy cases for disease confirmation.RESULTS: New cases of leprosy were diagnosed in the case group (n = 7, 8.6%), but not the control group.CONCLUSIONS: The new surveillance strategy is inexpensive, efficient, and feasible within a primary health strategy. Future studies can help improve the use of the SIF.

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ABSTRACT: Background: Childhood is a critical time for social and emotional development, educational progress and mental health prevention. Mental health for children and adolescents is defined by the achievement of expected developmental, cognitive, social and emotional skills. The development of child-adolescent mental health services (CAMHS) is a necessity for each country, not only as a prevention measure for the wellbeing of people, but also as an investment to the future of countries. Qualitative evaluation of services is the only way to ensure whether services function under quality standards and increase the possibility of better outcomes for their patients. This study examines the greek outpatient CAMHS against the British Standards of National Institute of Excellence for community CAMHS. The Standards assessed refer to the areas of Assessment, Care and Intervention. Objectives: The main objectives of the study are 1) to evaluate Greek outpatient CAMHS in the Attica region 2) to promote the evaluation process for mental health services in Greece. Methods: Due to the fact that Greek services are based on the British model, the tool used was the British self-review questionnaire of Quality Network for Community CAMHS(QNCC).The tool was translated, adapted and posted to services. Twelve out of twenty outpatient CAMHS of Attica (including Athens) responded. Data was collected and performed by the Statistical Package for Social Sciences SPSS. Results: The study resulted that the CAMHS examined, meet moderately the British Standards of 1) Referral and Access, 2) Assessment & Care planning, 3) Care & Intervention. Two out of twelve services examined, meet the standards of "Assessment and Care" in a higher percentage between 75% and 100%. Conclusions: The paper describes a satisfactory function of CAMHS in Attica prefecture taking into consideration the extremely difficult political situation of Greece at the time of the research. Strong and weak domains are identified. Also the translation and adaptation of British tools promote the evaluation process and quality assurance of Greek CAMHS.

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RESUMO: O Ministério da Saúde do Governo do Ruanda identifica a saúde mental como uma área de prioridade estratégica para a intervenção em resposta à alta carga dos transtornos mentais no Ruanda. Ao longo dos últimos 20 anos após o genocídio, o sector público reconstruiu sua Resposta Nacional de Saúde Mental com base no acesso equitativo aos cuidados, através do desenvolvimento de uma Política Nacional de Saúde Mental e novas estruturas de saúde mental. A política de Saúde Mental do Ruanda, revista em 2010, prima pela descentralização e integração dos serviços de saúde mental em todas as estruturas nacionais do sistema de saúde e ao nível da comunidade. O presente estudo de caso tem como objetivo avaliar a situação do sistema de saúde mental de um distrito típico de uma área rural no Ruanda, e sugerir melhorias, incluindo algumas estratégias para monitoras as mudanças. Os resultados do estudo permitirão ao Ruanda reforçar a sua capacidade para implementar o Plano Nacional de Saúde Mental ao nível dos distritos. O relatório também será útil para monitorar o progresso da implementação de serviços de saúde mental nos distritos, incluindo a prestação de serviços de base comunitária e a participação dos usuários, suas famílias e outros interessados na promoção, prevenção, assistência e reabilitação em saúde mental. Este estudo também procurou avaliar o progresso da implementação dos cuidados de saúde mental a nível descentralizado, com vista a compreender as implicações em termos de recursos desses processos. Foi realizada uma análise situacional num local do distrito, baseado em entrevistas com as principais partes interessadas responsáveis, usando o Instrumento de Avaliação de Sistemas de Saúde Mental da Organização Mundial da Saúde (WHO-AIMS). Os resultados sugerem que os recursos humanos para a saúde mental e serviços de base comunitária de saúde mental no distrito continuam a ser extremamente limitados. Os profissionais de saúde mental são adicionalmente limitados na sua capacidade para oferecer intervenções de emergência a pacientes psiquiátricos e garantir a continuidade do tratamento farmacológico a pacientes com condições crônicas. Para planejar efetivamente, de acordo com as necessidades da comunidade, sugerimos que o sistema de saúde mental deve envolver também os representantes das famílias e dos usuários no processo de planificação de modo a melhorar a sua contribuição no processo de implementação das atividades de saúde mental. Este estudo de caso do Distrito de Bugesera oferece a primeira análise de nível distrital dos serviços de saúde mental no Ruanda, e pode servir como uma mais-valia para a melhoria do sistema de saúde mental, incluindo a advocacia para a melhoria da qualidade dos cuidados de saúde mental a este nível, aumentando o financiamento para a implementação de serviços clínicos de saúde mental e os recursos humanos disponíveis para a prestação de cuidados de saúde mental, principalmente a nível dos cuidados primários.--------------------- ABSTRACT: To deal with the high burden of mental health disorders resulting from consequences of the 1994 genocide against Tutsis, the Rwanda Ministry of Health (MoH) considers mental health as a priority intervention. For the last 20 years, Ministry of Health focused on rebuilding a national and equity-oriented mental health program responding to the population needs in mental health. Mental health services are now decentralized and integrated in the national health system, from the community level up to the referral level. This study assessed the situation of mental health services in one rural district in Rwanda. It was aimed at assessing the progress of implementation of mental health care at the decentralized level, focusing on resource implications and processes. This study is based on interviews conducted with key stakeholders, using the World Health Organization's Assessment Instrument for Mental Health Systems (WHO-AIMS). Findings show that human resources for mental health care and community-based mental health services of the assessed district remain extremely limited. Mental health professionals face limitation regarding the ability to provide emergency management of psychiatric patients and to ensure continuity of psychopharmacological treatment of patients with chronic conditions. To improve the implementation process of mental health interventions and activities, a planning process based on community needs and the involvement of representatives of families and users in planning process should be considered. The Bugesera case study on the situation of mental health services can serve as a baseline for improvement of the mental health program in Rwanda, in terms of quality care services, infrastructure and equipment, human and financial resources.

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RESUMO: O Royal College of Psychiatrists tem um programa de voluntariado internacional desde 2005. O interesse no Reino Unido tem crescido nos últimos 15 anos com muitos projetos novos. Os benefícios para vários países têm sido reconhecidos. O que está menos claro são os benefícios da experiência para o Reino Unido e do programa de voluntariado do Royal College of Psychiatrists. O objectivo desta dissertação é explorar os benefícios do voluntariado para o Sistema Nacional de Saúde focando principalmente, mas não exclusivamente, o programa de voluntariado do Royal College of Psychiatrists. Nesta dissertação abordamos primeiro o contexto antes de discutirmos dois grandes estudos de psiquiatras e hospitais do Sistema Nacional de Saúde no Reino Unido. Incluimos no estudo todos os psiquiatras registados como Voluntários no Royal College of Psychiatrists e o Grupo de Interesse Especial associado. Foi ainda possível incluir os Diretores Médicos de todos os hospitais do Reino Unido. Os estudos foram desenhados para analisar as opiniões dos Voluntários do Reino Unido sobre os benefícios para os países recetores de baixo e médio rendimento e para o Reino Unido. Todos os 60 hospitais do Sistema Nacional de Saúde foram incluí dos para analisar a opinião sobre Voluntariado. As limitações dos estudos foram a baixa taxa de resposta, mas esta foi comparável a outros estudos do College. É provável haver um enviezamento de resposta e favorecimento dos que estão envolvidos no Voluntariado. Os resultados mostraram um interesse forte no voluntariado e benefícios no Sistema Nacional de Saúde, nas. áreas de liderança, transculturalismo, gestão e recursos e capacidades pessoais. Os hospitais do Sistema Nacional de Saúde valorizaram o voluntariado e, em contrapartida, o valor acrescido para competências profissionais. Os obstáculos contra o Voluntariado a nível individual e dos hospitais foram maioritariamente de natureza prática, tais como obter dispensa do trabalho, substituição no trabalho e custos. As implicações destes estudos são que o programa de voluntariado do College precisa de ser fortalecido. Para assegurar que este trabalho continua é necessário existir uma sensibilização nacional e maior responsabilização sobre os benefícios para o Reino Unido e a nível global. -------------------------- ABSTRACT: The Royal College of Psychiatrists has had an international volunteering programme since 2005. The interest in UK has grown over the past 15 years with many new projects. The benefits in various countries has been acknowledged. What has been less clear are the benefits of the experience back in the UK and of the Royal College of Psychiatrists Volunteer Scheme. The aim of this dissertation is to explore the benefit of volunteering to the NHS focusing mainly, but not exclusively on the Royal College of Psychiatrists Volunteering scheme. In this dissertation we first look at background information before discussing two large surveys of Psychiatrists and NHS Trusts in UK. We surveyed all those registered as Volunteers at the Royal College of Psychiatrists and the associated Special Interest Group. We also were able to survey the Medical Directors of all UK Trusts. The Surveys were designed to assess views of UK Volunteers of benefits to hosts in LMIC and back in UK. All 60 NHS Trusts were surveyed to assess the view of Volunteering. Limitation of the surveys were the low response rate but this was comparable to other College surveys. There is likely to be a bias in response and favour those who are engaged in the Volunteering agenda. Results showed a strong interest in volunteering and perceived benefits in NHS. These areas included leadership, transcultural, resource management and personal skills. NHS trusts valued volunteering and added value to professional competencies on return. Obstacles to Volunteering at individual and Trust level were mainly practical issues such as getting time off, cover and costs. Implications of these surveys are that the College volunteering scheme needs strengthening. There needs to be a National advocacy to ensure that this work continues and greater accountability as to benefits in UK and globally.

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Madine Darby Canine Kidney (MDCK) cell lines have been extensively evaluated for their potential as host cells for influenza vaccine production. Recent studies allowed the cultivation of these cells in a fully defined medium and in suspension. However, reaching high cell densities in animal cell cultures still remains a challenge. To address this shortcoming, a combined methodology allied with knowledge from systems biology was reported to study the impact of the cell environment on the flux distribution. An optimization of the medium composition was proposed for both a batch and a continuous system in order to reach higher cell densities. To obtain insight into the metabolic activity of these cells, a detailed metabolic model previously developed by Wahl A. et. al was used. The experimental data of four cultivations of MDCK suspension cells, grown under different conditions and used in this work came from the Max Planck Institute, Magdeburg, Germany. Classical metabolic flux analysis (MFA) was used to estimate the intracellular flux distribution of each cultivation and then combined with partial least squares (PLS) method to establish a link between the estimated metabolic state and the cell environment. The validation of the MFA model was made and its consistency checked. The resulted PLS model explained almost 70% of the variance present in the flux distribution. The medium optimization for the continuous system and for the batch system resulted in higher biomass growth rates than the ones obtained experimentally, 0.034 h-1 and 0.030 h-1, respectively, thus reducing in almost 10 hours the duplication time. Additionally, the optimal medium obtained for the continuous system almost did not consider pyruvate. Overall the proposed methodology seems to be effective and both proposed medium optimizations seem to be promising to reach high cell densities.

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RESUMO: As células eucarióticas evoluíram um sistema de sinalização complexo que lhes permite responder aos sinais extracelulares e intracelulares. Desta forma, as vias de sinalização são essenciais para a sobrevivência da célula e do organismo, uma vez que regulam processos fundamentais, tais como o desenvolvimento, o crescimento, a imunidade, e a homeostase dos tecidos. A via de transdução de sinal Hedgehog (Hh) envolve o receptor Patched1 (Ptch1), que tem um efeito inibidor sobre a proteína Smoothened (Smo) na ausência dos seus ligandos, as proteínas Sonic hedgehog (Shh). Estas proteínas são reguladores fundamentais do desenvolvimento embrionário, como ilustrado pelas malformações drásticas observadas em embriões humanos e de murganho com perturbações da transdução de sinal da via Hh e que incluem polidactilia, defeitos craniofaciais e malformações ósseas. Igualmente importantes são as consequências da ativação inapropriada da via de sinalização Hh na formação de tumores. Curiosamente, os componentes desta via localizam-se nos cílios primários. Além disso, demonstrou-se que esta localização é crucial para a sinalização através da via Hh. Na presença dos ligandos, Ptch1 é internalizado e destinado a degradação ou sequestrado num compartimento da célula de onde não pode desempenhar o seu papel inibitório. A proteína Arl13b é uma pequena GTPase pertencente à família Arf/Arl da superfamília Ras de pequenas GTPases e foi implicada no síndrome de Joubert, uma ciliopatia caracterizada por ataxia congénita cerebelar, hipotonia, atrso mental e cardiopatia congénita. Murganhos deficientes para Arl13b, chamado hennin (hnn) morrem morrem prematuramente ao dia 13,5 de gestação (E13,5) e exibem anomalias morfológicas nos cílios que levam à interrupção da sinalização Hh. Além disso, a Arl13b está diretamente envolvida na regulação da via Hh, controlando a localização de vários componentes desta via nos cílios primários. Neste trabalho, mostramos que a Arl13b se localiza em circular dorsal ruffles (CDRs), que são estruturas de actina envolvidas em macropinocitose e internalização de recetores, e que regula a sua formação. Além disso, aprofundámos o conhecimento do processo de ativação da via de sinalização Hh, mostrando que as CDRs sequestram seletivamente e internalizam o recetor Ptch1. As CDRs formam-se minutos após ativação da via por ligandos Shh ou pelo agonista de Smo SAG e continuam a ser formadas a partir daí, sugerindo uma indução contínua da reorganização do citoesqueleto de actina quando a via está ativada. Observámos ainda que a inibição da formação de CDRs através do silenciamento de WAVE1, uma proteína necessária para a formação destas estruturas, resulta na diminuição da ativação da via de sinalização Hh. Além disso, o bloqueio da macropinocitose, que se segue ao fecho das CDRs, através do silenciamento de uma proteína necessária para a cisão de macropinossomas, nomeadamente a proteína BARS, tem um efeito semelhante. Estes resultados sugerem que as CDRs e a macropinocitose são necessárias para a ativação da via de sinalização Hh e indicam que esta via de internalização controla os níveis de sinal Hh. Durante o desenvolvimento, as células proliferativas dependem do cílio primário para a transdução de várias vias de sinalização. A via Hh induz a diferenciação do músculo cardíaco. Por conseguinte, os murganhos deficientes na via de sinalização Hh exibem uma variedade de defeitos de lateralidade, incluindo alteração do looping do coração, como pode ser visto em murganhos deficientes para Arl13b. Por conseguinte, investigámos o papel da Arl13b no desenvolvimento do coração. Mostramos que a Arl13b é altamente expressa no coração de embriões de murganho e de murganhos adultos ao nível do mRNA e da proteína. Além disso, o perfil de distribuição da Arl13b no coração segue o dos cílios primários, que são essenciais para o desenvolvimento cardíaco. Corações de murganhos hnn no estadio E12,5 mostram um canal átrio-ventricular aberto, espessamento da camada compacta ventricular e aumento do índice mitótico no ventrículo esquerdo. Além disso, um atraso de 1 a 2 dias no desenvolvimento é observado em corações de murganhos hnn, quando comparados com controlos selvagens no estadio E13,5. Assim, estes resultados sugerem que a Arl13b é necessária para o desenvolvimento embrionário do coração e que defeitos cardíacos podem contribuir para a letalidade embrionária de murganhos hnn. Em suma, foi estabelecido um novo mecanismo para a regulação dos níveis de superfície do recetor Ptch1, que envolve a remodelação do citoesqueleto de actina e a formação de CDRs após a ativação da via de sinalização Hh. Este mecanismo permite um feedback negativo que evita a repressão excessiva da via através da remoção de Ptch1 da superfície da célula. Além disso, determinou-se que uma mutação de perda de função na Arl13b causa defeitos cardíacos durante o desenvolvimento, possivelmente relacionados com a associação dos defeitos em cílios primários e na sinalização Hh, existentes em murganhos deficientes para Arl13b. A via de sinalização Hh tem tido um papel central entre as vias de sinalização, uma vez que a sua regulação é crucial para o funcionamento apropriada da célula. Assim, a descoberta de um novo mecanismo de tráfego através de macropinocitose e CDRs que controla a ativação e repressão da via de sinalização Hh traz novas perspetivas de como esta via pode ser regulada e pode ainda conduzir à identificação de novos alvos e estratégias terapêuticas. --------------------ABSTRACT: Eukaryotic cells have evolved a complex signaling system that allows them to respond to extracellular and intracellular cues. Signaling pathways are essential for cell and organism survival, since they regulate fundamental processes such as development, growth, immunity, and tissue homeostasis. The Hedgehog (Hh) pathway of signal transduction involves the receptor Patched1 (Ptch1), which has an inhibitory effect on Smoothened (Smo) in the absence of its ligands, the Sonic hedgehog (Shh) proteins. These proteins are fundamental regulators of embryonic development, as illustrated by the dramatic malformations seen in human and mouse embryos with perturbed Hh signal transduction that include polydactyly, craniofacial defects and skeletal malformations. Equally important are the consequences of inappropriate activation of the Hh signaling response in tumor formation. Interestingly, the components of this pathway localize to primary cilia. Moreover, it has been shown that this localization is crucial for Hh signaling. However, in the presence of the ligands, Ptch1 is internalized and destined for degradation or sequestered in a cell compartment where it no longer can play its inhibitory role. ADP-ribosylation factor-like (Arl) 13b, a small GTPase belonging to Arf/Arl family of the Ras superfamily of small GTPases has been implicated in Joubert syndrome, a ciliopathy characterized by congenital cerebellar ataxia, hypotonia, intellectual disability and congenital heart disease. Arl13b-deficient mice, called hennin (hnn) die at embryonic day 13.5 (E13.5) and display morphological abnormalities in primary cilia that lead to the disruption of Hh signaling. Furthermore, Arl13b is directly involved in the regulation of Hh signaling by controlling the localization of several components of this pathway to primary cilia. Here, we show that Arl13b localizes to and regulates the formation of circular dorsal rufles (CDRs), which are actin-basedstructures known to be involved in macropinocytosis and receptor internalization. Additionally, we extended the knowledge of the Hh signaling activation process by showing that CDRs selectively sequester and internalize Ptch1 receptors. CDRs are formed minutes after Hh activation by Shh ligands or the Smo agonist SAG and keep being formed thereafter, suggesting a continuous induction of actin reorganization when the pathway is switched on. Importantly, we observed that disruption of CDRs by silencing WAVE1, a protein required for CDR formation, results in down-regulation of Hh signaling activation. Moreover, the blockade of macropinocytosis, which follows CDR closure, through silencing of a protein necessary for the fission of macropinosomes, namely BARS has a similar effect. These results suggest that CDRs and macropinocytosis are necessary for activation of Hh signaling and indicate that this pathway of internalization controls Hh signal levels. During development, proliferating cells rely on the primary cilium for the transduction of several signaling pathways. Hh induces the differentiation of cardiac muscle. Accordingly, Hh-deficient mice display a variety of laterality defects, including alteration of heart looping, as seen in Arl13b-deficient mice. Therefore, we investigated the role of Arl13b in heart development. We show that Arl13b is highly expressed in the heart of both embryonic and adult mice at mRNA and protein levels. Also, Arl13b localization profile mimics that of primary cilia, which have been shown to be essential to early heart development. E12.5 hnn hearts show an open atrioventricular channel, increased thickening of the ventricular compact layer and increased mitotic index in the left ventricle. Moreover, a delay of 1 to 2 days in development is observed in hnn hearts, when compared to wild-type controls at E13.5. Hence, these results suggest that Arl13b is necessary for embryonic heart development and that cardiac defects might contribute to the embryonic lethality of hnn mice. Altogether, we established a novel mechanism for the regulation of Ptch1 surface levels, involving cytoskeleton remodeling and CDR formation upon Hh signaling activation. This mechanism allows a negative feedback loop that prevents excessive repression of the pathway by removing Ptch1 from the cell surface. Additionally, we determined that the Arl13b loss-offunction mutation causes cardiac defects during development, possibly related to the associated ciliary and Hh signaling defects found in Arl13b-deficient mice. Hh signaling has taken a center stage among the signaling pathways since its regulation is crucial for the appropriate output and function of the cell. Hence, the finding of a novel trafficking mechanism through CDRs and macropinocytosis that controls Hh signaling activation and repression brings new insights to how this pathway can be regulated and can lead to the discovery of novel therapeutic targets and strategies.

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A presente dissertação tem como objectivo a elaboração de uma biografia do psiquiatra Luís Cebola, com ênfase na sua concepção da prática clínica e no seu posicionamento ideológico. Além disso, pretende-se ampliar a compreensão acerca da conceptualização da doença mental, bem como dos tratamentos psiquiátricos aplicados em Portugal, durante a primeira metade do século XX, tendo por base o seu desempenho enquanto director clínico – desde 1911 até 1949 – da Casa de Saúde do Telhal (CST), pertencente à Ordem Hospitaleira de São João de Deus (OHSJD). Esta dissertação representa um estudo pioneiro sobre esta personalidade – negligenciada pela história da psiquiatra praticada até agora em Portugal – e sobre as suas contribuições para o desenvolvimento da psiquiatria portuguesa, bem como para a disseminação-popularização de temas médicos e científicos. Demonstra-se que os tratamentos aplicados na CST, sob a sua direcção clínica, se mantiveram actualizados, tanto em relação aos outros hospitais psiquiátricos portugueses como em relação às instituições estrangeiras. As viagens que Cebola realizou a hospitais psiquiátricos de diversos países europeus, muito contribuíram para a modernização do ambiente hospitalar e terapêutico da CST, bem como para o seu privilegiar da terapia ocupacional – a ergoterapia – enquanto método de tratamento. Conclui-se que o esquecimento do médico por parte dos seus colegas de profissão, bem como pelos estudos históricos da disciplina, se deverá principalmente a três factores: em primeiro lugar, Cebola não desenvolveu projectos de investigação, e, por conseguinte manteve-se afastado das publicações da especialidade, bem como dos debates científicos da época; em segundo lugar, não formou discípulos, não dando, desse modo, continuidade à sua visão da prática clínica; e por último, as suas publicações de crítica sociopolítica, censurando o regime do Estado Novo, a Igreja Católica, e a psicocirurgia, criaram plausivelmente uma relação de tensão com os Irmãos da OHSJD e com a nova geração de psiquiatras.

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In the early nineties, Mark Weiser wrote a series of seminal papers that introduced the concept of Ubiquitous Computing. According to Weiser, computers require too much attention from the user, drawing his focus from the tasks at hand. Instead of being the centre of attention, computers should be so natural that they would vanish into the human environment. Computers become not only truly pervasive but also effectively invisible and unobtrusive to the user. This requires not only for smaller, cheaper and low power consumption computers, but also for equally convenient display solutions that can be harmoniously integrated into our surroundings. With the advent of Printed Electronics, new ways to link the physical and the digital worlds became available. By combining common printing techniques such as inkjet printing with electro-optical functional inks, it is starting to be possible not only to mass-produce extremely thin, flexible and cost effective electronic circuits but also to introduce electronic functionalities into products where it was previously unavailable. Indeed, Printed Electronics is enabling the creation of novel sensing and display elements for interactive devices, free of form factor. At the same time, the rise in the availability and affordability of digital fabrication technologies, namely of 3D printers, to the average consumer is fostering a new industrial (digital) revolution and the democratisation of innovation. Nowadays, end-users are already able to custom design and manufacture on demand their own physical products, according to their own needs. In the future, they will be able to fabricate interactive digital devices with user-specific form and functionality from the comfort of their homes. This thesis explores how task-specific, low computation, interactive devices capable of presenting dynamic visual information can be created using Printed Electronics technologies, whilst following an approach based on the ideals behind Personal Fabrication. Focus is given on the use of printed electrochromic displays as a medium for delivering dynamic digital information. According to the architecture of the displays, several approaches are highlighted and categorised. Furthermore, a pictorial computation model based on extended cellular automata principles is used to programme dynamic simulation models into matrix-based electrochromic displays. Envisaged applications include the modelling of physical, chemical, biological, and environmental phenomena.