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P -even, C P-violating signals in scalar-mediated processes
Get PDFMost studies of Higgs sector CP violation focus on the detection of CP-violating neutral Higgs-fermion Yukawa couplings, which yield P-odd, CP-violating phenomena. There is some literature on purely bosonic signatures of Higgs sector CP violation, where the simultaneous observation of three processes (suitably chosen) constitutes a signal of P-even CP violation. However, in the examples previously analyzed, some of the processes are strongly suppressed in the approximate Higgs alignment limit (corresponding to the existence of a Standard Model-like Higgs boson as suggested by LHC data), in which case the proposed CP-violating signals are difficult to observe in practice. In this paper, we extend the existing literature by examining processes that do not vanish in the Higgs alignment limit and whose simultaneous observation would provide unambiguous evidence for scalar-mediated P-even CP violation. We assess the discovery potential of such signals at various future multi-TeV lepton (and γγ) colliders. The potential for detecting loop-induced P-even,
CP-violating phenomena is also considered.info:eu-repo/semantics/publishedVersio
What happens in performers' minds?: dancers' and musicians' inner conversations
Get PDFABSTRACT - This article aims to describe and understand what performers think about during performances and
rehearsals while searching for a common language between music and dance.
Departing from our own experiences as performers (a dancer and a musician), we ask the question
what do we think about when we are dancing/playing? We assume that this awareness of what we
think while performing is not obvious and decided to explore this by interviewing six dancers and
six musicians about what we named performers’ ‘inner conversations.’
Within a phenomenological orientation, we developed a descriptive and interpretative study of a
phenomenon (inner conversations) which gives itself to conscience, a pre-reflective consciousness.
From the performers’ accounts, we extrapolated four trends: 1. Variation in awareness of inner
conversations; 2. Altered states of awareness; 3. Parasitic inner conversations; and 4. Overcoming
internal difficulties and external constraints through inner conversations.
Looking at the dancers’ and musicians’ accounts together raised the question: How is the
awareness of ‘inner conversations’ developed during performers’ initial education and training?Este artigo tem como objetivo descrever e compreender o que pensam os performers durante as apresentações e ensaios, na busca de uma linguagem comum entre música e dança.
Partindo de nossas próprias experiências como performers (dançarino e músico), fazemos a pergunta em que pensamos quando estamos dançando/tocando? Assumimos que essa consciência do que pensamos durante a performance não é óbvia e decidimos explorar isso entrevistando seis dançarinos e seis músicos sobre o que chamamos de 'conversas internas' dos performers.
Numa orientação fenomenológica, desenvolvemos um estudo descritivo e interpretativo de um fenómeno (conversas interiores) que se dá à consciência, uma consciência pré-reflexiva. A partir dos relatos dos performers, extrapolamos quatro tendências: 1. Variação na percepção das conversas internas; 2. Estados alterados de consciência; 3. Conversas internas parasitas; e 4. Superar dificuldades internas e restrições externas por meio de conversas internas.
Observar os relatos de dançarinos e músicos juntos levantou a questão: como a consciência das 'conversas internas' é desenvolvida durante a educação e treinamento inicial dos performers?N/
Factors affecting banking performance in Pakistan: an empirical investigation
Get PDFPakistan is one of the economically emerging countries in South
Asia. The current trends of Pakistan’s economy are on the path to
outshining the former year’s growth rate. The unrelenting perfor-
mances in the agriculture and services sector and outperformance of
the large-scale manufacturing sector. Inflation and the fiscal deficit
were confined, whereas revenue growth has surpassed last year’s
level. However, Pakistan’s populace is 200 million. However, not
many individuals bank with a regulated banking system. The financial system in Pakistan introduced a new phenomenon of the Islamic
Banking system that is not a recent idea but has been in the mainstream now for more than a decade. There are several factors internally and externally that stimulate the performance of banks. In this
paper, we have tried to investigate how these factors influence the
performance of banks in Pakistan. We have used the ROE measure
as a dependent variable to evaluate banks' profitability. We have
taken the size, age, equity and financial development of the banks.
Some external/country-specific factors are also taken into consideration as independent variables. This paper uses panel data from six banks in Pakistan for seven years (2010 to 2017).info:eu-repo/semantics/publishedVersio
Desenvolvimento de uma rede neuronal de convolução para reconhecimento de hérnias discais em imagens de ressonância magnética
Get PDFMestrado em Radiações Aplicadas às Tecnologias da Saúde - Área de especialização: Imagem por Ressonância MagnéticaIntrodução: A hérnia discal lombar (HDL) é, atualmente, a causa mais frequente da radiculopatia lombar nos adultos jovens. A IA é considerada “a tecnologia que define o futuro”, pelo que é extremamente pertinente demonstrar a fiabilidade do uso desta tecnologia de elevado potencial no diagnóstico de HDL, fazendo uso da técnica imagiológica de maior sensibilidade e acurácia diagnóstica, a ressonância magnética. Objetivos: O objetivo principal deste trabalho é desenvolver e treinar uma rede neuronal de convolução (CNN) destinada a auxiliar o diagnóstico de HDL, tendo por base imagens de ressonância magnética da coluna lombar no plano axial. Métodos: O desenho de estudo é de carácter descritivo e estatístico, secundário, de recuperação e análise crítica da literatura. No total, foram recolhidas e analisadas 48 345 imagens totais de ressonância magnética da coluna lombar, referentes a 515 utentes, as quais se encontram disponíveis numa base de dados pública. Destas imagens, escolheram-se 3 172 ponderadas em T2 e referentes aos planos axial e sagital. Posteriormente, recorrendo a um algoritmo de data augmentation, foram geradas 35 600 imagens desenvolver destinadas a treinar e validar duas CNN (VGG16 e VGG19). Resultados: Foram alcançados excelentes valores de accuracy durante a validação das redes, com os melhores resultados a chegarem a cerca de 0,9; estes resultados foram acompanhados de funções de loss decrescentes no processo de validação que atingiram valores de 0,5. Conclusões: O contributo deste trabalho pode ser importante para o desenvolvimento de um algoritmo capaz de detetar HDL em imagens de ressonância magnética com uma precisão muito próxima da executada pelos profissionais de saúde mais experientes.ABSTRACT - Introduction: Lumbar disc herniation is currently the most frequent cause of lumbar radiculopathy in young adults. Artificial intelligence is considered “the technology that defines the future”, so it is extremely pertinent to demonstrate the reliability of the use of this high-potential tool in the diagnosis of lumbar disc herniations, through the imaging method of greater sensitivity and diagnostic accuracy, magnetic resonance imaging. Objectives: The main objective of this work is to demonstrate the applicability and reliability of convolutional neural networks in the diagnosis of lumbar disc hernias through the application of a convolutional neural network in magnetic resonance imaging. Methods: The study design is descriptive and statistical, secondary, recovery, and critical analysis of the literature. In total, 48 345 magnetic resonance images of the lumbar spine available in a public database were collected and analyzed, referring to 515 users. Of these images, 3 172 T2 – T2-weighted were chosen and referred to the axial and sagittal planes. Subsequently, using a data augmentation algorithm, 35,600 were selected to develop, train, and validate the CNN based on the VGG16 network. Results: Excellent accuracy values were achieved during network validation, reaching 0,9. The best loss function values in the validation process were 0,5. Conclusions: After the application of a convolutional neural network, it was found that this is a tool to be taken into account in the diagnosis of HDLs.N/
Plataforma de software para gestão dos doentes mentais internados em instituições do setor social no Hospital Fernando Fonseca.
Get PDFProjecto final para obtenção do Grau de Mestre em Engenharia Informática e de Computadores.O Hospital Fernando Fonseca e uma organização que trabalha com doentes com doenças mentais os quais são enviados para Casa de Saúde de modo a serem cuidados durante 24 horas por dia. Estes pacientes podem ser enviados para as Casas de Saúde por parte do próprio HFF ou por instituições externas. Quando um paciente entra numa Casa de Saúde, o HFF ou a instituição que enviou o paciente, é responsável pelo
pagamento dos cuidados diários deste paciente. Já dentro da Casa de Saúde, pode ser necessário que um paciente visite outras instituições, por exemplo hospitais. Durante este período, o HFF não pode ser cobrado pelo cuidado destes pacientes uma vez que estes não estão na Casa de Saúde. Dado que o HFF não controla estas saídas, podem ser cobrados dias nos quais o paciente não esteve na Casa de Saúde. O processo atual de referenciação de um paciente para uma Casa de Saúde, bem como a gestão do mesmo, e realizado de forma manual, através do envio de emails entre departamentos. Este processo pode ser lento e sujeito a falhas. O desenvolvimento deste projeto tem como objetivo a criação de uma aplicação que facilite a comunicação entre os diferentes departamentos envolvidos no processo de internamento, bem como simplificar a criação e gestão do processo e garantir que o HFF esta a ser cobrado o valor real dos cuidados. Neste documento serão apresentadas as diferentes fases de desenvolvimento do projeto tais como o levantamento de requisitos, a criação de mock-ups para exposição de ideias, criação de modelos de base de dados, criação da aplicação, testes realizados e por fim o deployment.Hospital Fernando Fonseca is an organization that manages patients with mental diseases sent to Care Houses that are able to take care of them for 24 hours a day. These patients can be sent to the Care Houses by the hospital itself or by other institutions. Once a patient has entered a Care House, the HFF is responsible for the payment of the daily cares of the patient. In case the patient comes from another institution, then it is the institution’s responsibility to make these payments. Once in the Care House, a patient might need to go to other institutions, such as hospitals, for other health related reasons. During these days, the care of the patients should not be billed since they are not in the Care House. This however, poses a problem because the HFF cannot track these visits since they are only managed by the Care House, which can lead to the days being billed without the knowledge of the HFF. The current process of referring a patient to a Care House and managing their internment is made manually, and the communication between the HFF and the Care Houses is made via e-mail. This makes the process slow and prone to failure. The development of this project has the goal of creating and application that will allow the different departments that take part in this process to communicate better with
each other in order to simplify the process and guarantee the correct billing for the care of the patients. This document will present the different stages of the development of the project, such as defining the requirements, creating a set of mock-ups to explain the ideas to the HFF, developing the database models, creating the application, testing it and finally deploying it.N/
microRNA-122 and microRNA-1247 regulate the pathogenic phenotype of effector CD4+ T cell subsets in (auto)immune responses in vivo
No full textAutoimmune diseases are often associated with an imbalance between CD4+ T cell subsets, namely pro-inflammatory effector cells, including T helper 1 (Th)1 and Th17 cells (IFN-γ- and IL-17-producers, respectively), and anti-inflammatory Foxp3+ regulatory cells (Treg). The differentiation of these distinct CD4+ T cell subsets is known to be regulated by microRNAs (miRNAs), small non-coding RNAs that fine-tune gene expression at the post-transcriptional level. While various individual miRNAs have been implicated in this process, a holistic approach focused on in vivo immune responses is missing to better understand how miRNA networks shape the CD4+ T cell compartment in pathophysiology. To address this biological question, we established a triple reporter mouse for Ifng, Il17, and Foxp3, and subjected it to experimental autoimmune encephalomyelitis (EAE), a widely used rodent model of Multiple Sclerosis (MS). We performed miRNA-seq analysis on Th1, Th17, and Treg cells isolated from the spleen and lymph nodes (LNs) at the peak-plateau stage of EAE, and found 110 miRNAs to be differentially expressed between the effector and regulatory subsets. From there, we studied the functional role of 5 candidate miRNAs as they were specifically upregulated in one population versus the others. In vivo miRNA modulation showed that silencing miR-122 (upregulated in Th17 cells) increased the frequency of IL-17A+ cells in the LNs and precipitated the onset of EAE, whereas upregulation of miR-1247 (highly expressed in the Th1 subset) decreased the severity of the disease reducing the number of IFN-γ+ cells in the LNs. We further found that both IL-6 and TGF-β induce miR-122 expression, whereas IL-23 and IL-1β repress its expression. Given that IL-23 and IL-1β are critical to induce Th17-mediated pathogenicity, our data suggests that miR-122 is expressed in a non-pathogenic context. Interestingly, we have observed a pathogenic gene signature in CNS-derived Th17 cells (when compared to peripheral Th17 cells) with concomitantly decreased levels of miR-122, suggesting that miR-122 may regulate Th17 pathogenicity. Similarly, we observed that once Th1 cells infiltrate the CNS, their levels of miR-1247 decrease, and they produce higher levels of IFN-γ. Furthermore, as we found that this miRNA is induced by the anti-inflammatory cytokines IL-10 and TGF-β, we propose that miR-1247 constitutes an auto-regulatory mechanism of Th1 cells in the periphery, which is disrupted upon CNS infiltration. Overall, our results suggest that miR-122 and miR-1247 control the pathogenic phenotype of effector Th17 and Th1 cells, respectively, during CNS autoimmunity. These findings may have important implications for autoimmune diseases, which we are now assessing in samples from MS patients.info:eu-repo/semantics/publishedVersio
Joining of fibre-reinforced thermoplastic polymer composites by friction stir welding—A review
Get PDFThe objective of the current work is to show the potential of the friction stir welding (FSW) and its variants to join fibre-reinforced thermoplastic polymer (FRTP) composites. To accomplish that, the FSW technique and two other important variants, the friction stir spot welding (FSSW) and the refill friction stir spot welding (RFSSW), are presented and explained in a brief but complete way. Since the joining of FRTP composites by FSSW has not yet been demonstrated, the literature review will be focused on the FSW and RFSSW techniques. In each review, the welding conditions and parameters studied by the different authors are presented and discussed, as well as the most important conclusions taken from them. About FSW, it can be concluded that the rotational speed and the welding speed have great influence on heat generation, mixture quality, and fibre fragmentation degree, while the tilt angle only has residual influence on the process. The reduction of internal and external defects can be achieved by adjusting axial force and plunge depth. Threaded or grooved conical pins achieved better results than other geometries. Stationary shoulder tools showed better performance than conventional tools. Regarding the RFSSW, it has not yet been possible to deepen conclusions about most of the welding parameters, but its feasibility is demonstrated.info:eu-repo/semantics/publishedVersio
Blockchain for smart grid security: applications, trends, and challenges
No full textThe electric power grid is the world's largest engineering system, and its secure and reliable operation is vital to human activities. The introduction of intelligence in the electrical power grid through smart grids imposes challenges that require new techniques and approaches to provide cyber-physical security. In this article, we discuss the use of blockchain to provide security and reliability to smart grids. Blockchain allows untrusted nodes to correctly and verifiably interact with each other in a distributed peer-to-peer network, without any reliable intermediary. We explore smart contracts, codes resident in blockchain that automate multi-step processes, as a way to automatically trade electric energy. We also discuss initiatives, challenges, and research opportunities of blockchain technologies in the electrical sector.info:eu-repo/semantics/publishedVersio
Thermo-mechanical modelling of the Friction Stir Spot Welding process: Effect of the friction models on the heat generation mechanisms
No full textFriction Stir Spot Welding involves complex physical phenomena, which are very difficult to probe experimentally. In this regard, the numerical simulation may play a key role to gain insight into this complex thermo-mechanical process. It is often used to mimic specific experimental conditions to forecast outputs that may be substantial to analyse and elucidate the mechanisms behind the Friction Stir Spot Welding process. This welding technique uses frictional heat generated by a rotating tool to join materials. The heat generation mechanisms are governed by a combination of sliding and sticking contact conditions. In the numerical simulation, these contact conditions are thoroughly dependent on the used friction model. Hence, a successful prediction of the process relies on the appropriate selection of the contact model and parameters. This work aims to identify the pros and cons of different friction models in modelling combined sliding-sticking conditions. A three-dimensional coupled thermo-mechanical FE model, based on a Coupled Eulerian-Lagrangian formulation, was developed. Different friction models are adopted to simulate the Friction Stir Spot Welding of the AA6082-T6 aluminium alloy. For these friction models, the temperature evolution, the heat generation, and the plastic deformation were analysed and compared with experimental results. It was realized that numerical analysis of Friction Stir Spot Welding can be effective and reliable as long as the interfacial friction characteristics are properly modelled. This approach may be used to guide the contact modelling strategy for the simulation of the Friction Stir Spot Welding process and its derivatives.info:eu-repo/semantics/publishedVersio
Determinants of children's food choices in fast-food restaurants
Get PDFFCT_UIDP/05748/2020. FCT_UIDB/04470/2020. FCT_UIDB/05608/2020. FCT_UIDP/05608/2020.Nos últimos anos, verificou-se uma alteração no ritmo de vida da população, que se traduziu numa mudança dos hábitos de consumo, com um aumento do consumo de refeições fora de casa, incluindo pelas crianças. Na maioria das vezes, os locais escolhidos para realizar as refeições são os restaurantes de fast-food. Geralmente as refeições preparadas neste tipo de restaurantes, incluindo as refeições infantis, têm uma qualidade nutricional muito baixa. O comportamento das crianças em relação às suas escolhas alimentares, é afetado por vários determinantes de consumo, pelo que o principal objetivo deste estudo foi identificar os determinantes das escolhas alimentares infantis em restaurantes de fast-food. De forma a atingir este objetivo, foi elaborado um questionário, disponibilizado online dirigido a pais de crianças com idades compreendidas entre os 6 e os 12 anos. Observou-se que para as crianças, os fatores determinantes na escolha do restaurante de fast-food e da refeição consumida, foram, por ordem de importância: a oferta de um brinquedo colecionável/promocional, as opções disponíveis e o sabor agradável da refeição. Para os pais, os fatores mais relevantes no momento da escolha do restaurante de fast-food e da refeição infantil consumida, foram a conveniência do local, o preço acessível, o sabor agradável e as preocupações com a saúde, respetivamente. Os resultados deste estudo evidenciam a necessidade de reformular e desenvolver refeições infantis equilibradas sem comprometer a palatabilidade, associando a estas opções equilibradas a oferta de brindes colecionáveis.ABSTRACT - In recent years people are eating more out of home, and children are no exception. Most often, the places chosen to have meals away from home are fast-food restaurants. Generally, foods prepared in this type of restaurant, including children's menus, have a very poor nutritional quality. The behavior that each child has in relation to their food choices is a process that is affected by several determinants of consumption. The main objective of this study is to identify the determinants of children's food choices in fast-food restaurants. To achieve these objectives, an online questionnaire, directed to parents with children aged between 6 and 12 years old, was developed and applied. It was observed that for children, the determinant factors in choosing the fast-food restaurant and the meal consumed were, in order of importance: the offer of a collectible / promotional toy, the options available, and the pleasant taste of the meal. For parents, the most relevant factors when choosing the fast-food restaurant and the consumed children's meal were the convenience of the place, the affordable price, the pleasant taste, and the health concerns, respectively. There were some contradictory results that were indicative of parents' illiteracy in terms of food and nutrition, which also highlighted the need to apply measures to encourage the choice of healthier children's meals in fast-food restaurants. The results of this study show the need to reformulate and develop balanced children's meals without compromising palatability, associating these balanced options with the offer of collectible gifts.info:eu-repo/semantics/publishedVersio