WAVELET BASED NONLINEAR SEPARATION OF IMAGES

This work addresses a real-life problem corresponding to the separation of the nonlinear mixture of images which arises when we scan a paper document and the image from the back page shows through. The proposed solution consists of a non-iterative procedure that is based on two simple observations: (1) the high frequency content of images is sparse, and (2) the image printed on each side of the paper appears more strongly in the mixture acquired from that side than in the mixture acquired from the opposite side. These ideas had already been used in the context of nonlinear denoising source separation (DSS). However, in that method the degree of separation achieved by applying these ideas was relatively weak, and the separation had to be improved by iterating within the DSS scheme. In this paper the application of these ideas is improved by changing the competition function and the wavelet transform that is used. These improvements allow us to achieve a good separation in one shot, without the need to integrate the process into an iterative DSS scheme. The resulting separation process is both nonlinear and non-local. We present experimental results that show that the method achieves a good separation quality

Effects of different ways of polymerization of an universal adhesive in shear bond strength to dentin

Tese de mestrado, Medicina Dentária, Universidade de Lisboa, Faculdade de Medicina Dentária, 2018Objectives: The aim of this in vitro study was to understand the influence of the curing mode of an universal adhesive system, applied according to etch-and-rinse (ER) and self-etch (SE) strategies, in the shear bond strength to dentin. Materials and methods: 20 healthy teeth were selected and sectioned in a way that originated 40 specimens. These were randomly distributed in 4 groups: SE independent- pre-curing of the adhesive used with a SE strategy; SE co-polymerization- co-polymerization of the composite and the adhesive used with a SE strategy; ER independent- pre-curing of the adhesive used with an ER strategy; ER co-polymerization- co-polymerization of the composite and the adhesive used with an ER strategy. After 24 h incubation period, the shear bond strength tests were performed. Normality and homogeneity of the data were evaluated by Shapiro-Wilk test and Levene test, respectively, and a one-way ANOVA was used. Results: Specimens from group SE independent yielded the higher shear bond strength values comparing to the values obtained with the specimens from the other groups (p<0,05). Shear bond strength values from specimens of Groups SE co-polymerization, ER independent and ER co-polymerization where not significantly different. The most common failure mode in specimens from group SE independent was mixed, while adhesive failure was prevalent among the other groups. Conclusion: The separate polymerization of the universal adhesive with a SE approach and first layer of composite lead to the best bond strength values to dentin

Feature engineering: técnicas e aplicações

Machine Learning is a rising concept in today's society. In the past decade, ML-based systems have become part of people's daily routines, and their usage has been disseminated through diverse sectors. This evolution is supported by the exponential increase in data created worldwide. Feature Engineering is a critical process focused on transforming data into suitable inputs for Machine Learning algorithms. This work explores the Feature Engineering process by developing a baseline for its implementation. Hence, a pipeline of Feature Engineering techniques and their taxonomy is proposed, along with a set of R scripts to implement. The validity of the code is then demonstrated through its application to a real-world dataset.MachineLearning é um conceito em crescente evolução na sociedade atual. Na última década, os sistemas baseados em ML tornaram-se parte do quotidiano da população e a sua aplicação tem vindo a disseminar-se por diversos setores. Este crescimento é suportado pelo aumento exponencial da quantidade de dados gerados a nível mundial. FeatureEngineering surge, assim, como um processo chave que permite transformar dados em inputs adequados para os algoritmos de MachineLearning. O presente trabalho pretende explorar o processo de FeatureEngineering, com vista a desenvolver uma base de suporte à sua implementação. Por conseguinte, é proposta uma pipeline de técnicas de FeatureEngineering em paralelo com a sua taxonomia, juntamente com um conjunto de scripts R, para as implementar. A validade do código é, posteriormente, demonstrada através da sua aplicação a um conjunto de dados reais.info:eu-repo/semantics/publishedVersio

Continente online : the sale of online advertising

Continente Online is one of the online grocery stores in Portugal. Founded in 2001, Continente’s Online store provides a convenience service to customers, offering more than 30,000 grocery and non-grocery products. Focus will be applied on this Portuguese case of E-commerce, with special attention being given to its monetization businesses, namely the sale of online advertising to third parties that was launched in 2010. This case study consists on a strategic reflection on the potentialities and challenges of this business. To do this, market research was conducted with the aim of understanding the reasons and objectives inherent to this business of online advertising and to indentify and analyze the main differences between Continente’s Online store and its advertisers’ and customers’ perceptions and also the online’s store advertising campaigns. The findings suggest that Continente’s Online store aims at monetizing its E-commerce platform investment, providing extra information to customers and increasing sales. In line with this, advertisers aspire to increase its visibility, communicate their brands and also increase their sales. Moreover, although the click intentions reveal to be low, the online advertising campaigns analyzed show a positive relationship between clicks and results, emphasizing the need of implementing better and more detailed performance monitoring. In order to continue with this monetization in the future, Continente’s Online store still showed some room for improvement. Applying customized and one-to-one advertising strategies, investing in standard banners and being more conversions and performance oriented would be some recommendations done by the author.Continente Online é um dos supermercados online em Portugal. Fundado em 2001, o Continente Online oferece um serviço de conveniência, disponibilizando a todos os clientes mais de 30,000 produtos alimentares e não alimentares. Esta dissertação foca-se no caso Português de E-commerce, mais concretamente num dos negócios de monetização, ou seja, a venda de publicidade online a terceiros que se iniciou em 2010. Este caso de estudo consiste numa reflexão estratégica sobre as potencialidades e desafios deste negócio. Para tal, uma investigação de mercado foi realizada com o objetivo de compreender quais as razões e os objetivos inerentes a este negócio de publicidade online e identificar e analisar as principais divergências de acordo com as perceções do Continente Online, anunciantes e clientes. Os resultados obtidos sugerem que a loja do Continente Online visa rentabilizar o seu investimento em E-commerce, fornecer informações aos clientes e aumentar as vendas. Em consonância com isso, os anunciantes aspiram um aumento de visibilidade, comunicar marcas e também aumentar vendas. Além disso, apesar das intenções de clique estudadas terem revelado ser baixas, as campanhas de publicidade online em estudo demonstraram uma relação positiva entre cliques e resultados, enfatizando a necessidade de implementação de uma melhor e mais detalhada monitorização de desempenho. Para continuar com esta monetização no futuro, o Continente Online ainda mostrou algum espaço para melhorias. Aplicando estratégias de publicidade customizadas, investindo em formatos de publicidade estandardizados e estar mais focado em medidas de conversão e desempenho são algumas recomendações feitas pelo autor

Characterization of the glycans involved in sea urchin Paracentrotus lividus reversible adhesion

Sea urchins have hundreds of specialized adhesive organs, the tube feet, which play a key role in locomotion, substrate attachment and food capture. Tube feet are composed by two functional units: a proximal cylindrical stem that is mobile and flexible, attached to a distal flattened disc that produces adhesive secretions. Oral tube feet discs possess a specialized duo-glandular epidermis that produces adhesive and de-adhesive secretions, enabling strong but reversible adhesion to the substrate. Due to the growing interest in biomimetic adhesives, several studies have been carried out to characterize sea urchin adhesives, and up to date, it has been shown that it is composed by proteins and glycans. The protein fraction has been the subject of several studies, that pin-pointed several adhesion-related candidates. Contrastingly, little is known about the glycans that compose sea urchin adhesives. This study aims at contributing to this topic by focusing on the characterization of the glycosidic fraction of the adhesive secreted by the sea urchin Paracentrotus lividus (Lamarck, 1816), using a battery of 22 lectins, applied to 3 complementary techniques. Our results show that five lectins label exclusively the disc adhesive epidermis and simultaneously the secreted adhesive, being, therefore, most likely relevant for sea urchin adhesion. In addition, it was possible to determine that the glycosidic fraction of the adhesive is composed by a high molecular weight glycoprotein containing N-acetylglucosamine oligomers.info:eu-repo/semantics/publishedVersio

Cytomegalovirus Pulmonary Involvement in an Immunocompetent Adult

Cytomegalovirus (CMV) is a linear double-stranded DNA virus that may cause severe and potentially fatal infection in immunocompromised hosts. In immunocompetent individuals, the infection is typically mild or asymptomatic. However, in the last years, some cases of severe cytomegalovirus infection in immunocompetent individuals have been described. Clinical Presentation. 'e authors present a male patient aged 42 years, without specific medical history, who presented a 15-day history of fever, headache, night sweats, odynophagia, and bilateral otalgia, without improvement after four days of therapy with amoxicillin/clavulanic acid. Blood count and biochemistry were performed with liver cytolysis pattern. Chest teleradiography showed diffuse interstitial infiltrate. 'oracic CT scan revealed areas in a ground glass with a cross-linking component in the left and right upper lung lobes compatible with an inflammatory/infectious process. Blood serology was positive for CMV IgG and IgM. 'e detection on blood and bronchoalveolar lavage of CMV DNA by polymerase chain reaction (PCR) was also positive. Ganciclovir was started based on the clinical features and the result of CMV serology. After 48 hours, there was a significant clinical improvement, with remission of fever, and he was discharged on the 13th day of hospitalization with oral valganciclovir, completing a 21-day antiviral course at home. Conclusion. With this clinical case, the authors highlight the importance of considering CMV infection in evaluating patients with pneumonia, even in immunocompetent ones, particularly in those with no clinical improvement with antibiotics instituted for bacterial pneumonia, and when other causes have been ruled outinfo:eu-repo/semantics/publishedVersio

COVID-19 risk perception and confidence among clinical dental students: impact on patient management

Communication abstract: Proceedings of the 5th International Congress of CiiEM - Reducing inequalities in Health and Society, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from June 16th to 18th, 2021.This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.This study aimed to assess COVID-19 perceived risk, confidence and its impact on potentially infected patients’ management practices, in a clinical dental education setting. The survey was conducted by application of a self-administered questionnaire amid the COVID-19 pandemic. Results indicate high COVID-19 perceived risk and confidence levels (86.7% and 72.8%, respectively). A significantly lower risk perception was identified for individuals classifying COVID-19 as a moderately dangerous disease and confidence was significantly lower for women and for individuals not previously exposed to confirmed or suspected cases of COVID-19. No factor-related significant differences were found on potentially infected patients’ management practices.info:eu-repo/semantics/publishedVersio

Efeitos de mediação do burnout e da perda de bem-estar

Objetivo: O Assédio psicológico no trabalho é uma preocupação crescente para gestores e trabalhadores, pelos efeitos negativos que tem na organização e na produtividade. Constitui também preocupação crescente para os profissionais de saúde pelos efeitos, por vezes devastadores, que têm sobre a saúde. No entanto, poucos estudos têm investigado a forma como o Assédio psicológico no trabalho se relaciona com o Burnout e a perda de Bem-estar e de como, no conjunto, afetam a produtividade dos trabalhadores, traduzida em formas de Presentismo. Assim, o objetivo do presente estudo foi examinar os efeitos de mediação, considerando a análise de relações diretas e indiretas, do Burnout e do Bem-estar psicológico na relação entre o Assédio no trabalho e a perda de produtividade devida a qualquer das dimensões do Presentismo (Trabalho não completado e Concentração). Método: Recorreu-se a modelos de equações estruturais (SEM) para análise de dados de um estudo transversal, recolhidos por Computer Assisted Web Interview – CAWI, referente a uma amostra de 353 trabalhadores de uma empresa portuguesa de serviços de âmbito nacional. Foram consideradas as seguintes variáveis: Assédio no trabalho (Quine, 1999), Burnout (MBI – Exaustão emocional), Bem-estar psicológico (GHQ-28) e as perdas de produtividade devido ao presentismo (SPS-6) (Trabalho não completado e Concentração). Todas as variáveis apresentaram características psicométricas aceitáveis. Resultados: O modelo final revelou um ajuste aceitável. Verificou-se que o assédio no trabalho teve um efeito significativo sobre o Presentismo por duas vias: diretamente, afetando a dimensão Trabalho não completado e indiretamente, afetando a Concentração. Esta última via foi mediada pelos efeitos do Burnout e pela perda de Bem-estar psicológico. Conclusões e recomendações: Os profissionais de saúde ocupacional devem estar cientes de que o Burnout e a perda de Bem-estar podem ter como causa primária o Assédio no trabalho e que as perdas de produtividade podem ser um sinal de alerta. Os gestores e as chefias devem ter em conta que, no mecanismo subjacente à perda de produtividade dos trabalhadores, poderão estar situações de Assédio no trabalho devido aos efeitos diretos e ao impacto negativo sobre o Burnout e Bem-estar.N/

Systematic Review

Funding Information: MP received support from the Portuguese National Funds through FITEC – Programa Interface, with reference CIT INOV – INESC INOVAÇÃO. Funding was also provided from the PhD program in Industrial Management, NOVA Science and Technology Faculty. Funding Information: MP and LVL acknowledge Fundação para a Ciência e a Tecnologia (FCT-MCTES) for its financial support via the project UIDB/00667/2020 (UNIDEMI).Background: The digital age, with digital sensors, the Internet of Things (IoT), and big data tools, has opened new opportunities for improving the delivery of health care services, with remote monitoring systems playing a crucial role and improving access to patients. The versatility of these systems has been demonstrated during the current COVID-19 pandemic. Health remote monitoring systems (HRMS) present various advantages such as the reduction in patient load at hospitals and health centers. Patients that would most benefit from HRMS are those with chronic diseases, older adults, and patients that experience less severe symptoms recovering from SARS-CoV-2 viral infection. Objective: This paper aimed to perform a systematic review of the literature of HRMS in primary health care (PHC) settings, identifying the current status of the digitalization of health processes, remote data acquisition, and interactions between health care personnel and patients. Methods: A systematic literature review was conducted using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines to identify articles that explored interventions with HRMS in patients with chronic diseases in the PHC setting. Results: The literature review yielded 123 publications, 18 of which met the predefined inclusion criteria. The selected articles highlighted that sensors and wearables are already being used in multiple scenarios related to chronic disease management at the PHC level. The studies focused mostly on patients with diabetes (9/26, 35%) and cardiovascular diseases (7/26, 27%). During the evaluation of the implementation of these interventions, the major difficulty that stood out was the integration of information into already existing systems in the PHC infrastructure and in changing working processes of PHC professionals (83%). Conclusions: The PHC context integrates multidisciplinary teams and patients with often complex, chronic pathologies. Despite the theoretical framework, objective identification of problems, and involvement of stakeholders in the design and implementation processes, these interventions mostly fail to scale up. Despite the inherent limitations of conducting a systematic literature review, the small number of studies in the PHC context is a relevant limitation. This study aimed to demonstrate the importance of matching technological development to the working PHC processes in interventions regarding the use of sensors and wearables for remote monitoring as a source of information for chronic disease management, so that information with clinical value is not lost along the way.publishersversionpublishe