Ripples and Grains Segregation on Unpaved Road

Ripples or corrugations are common phenomena observed in unpaved roads in less developed countries or regions. They cause several damages in vehicles leading to increased maintenance and product costs. In this paper, we present a computational study about the so-called washboard roads. Also, we study grain segregation on unpaved roads. Our simulations have been performed by the Discrete Element Method (DEM). In our model, the grains are regarded as soft disks. The grains are subjected to a gravitational field and both translational and rotational movements are allowed. The results show that wheels' of different sizes, weights and moving with different velocities can change corrugations amplitude and wavelength. Our results also show that some wavelength values are related to specific wheels' speed intervals. Segregation has been studied in roads formed by three distinct grain diameters distribution. We observed that the phenomenon is more evident for higher grain size dispersion

Retinal biomarkers of Alzheimer’s disease: insights from transgenic mouse models

In this paper, we use the retina as a window into the central nervous system and in particular to assess changes in the retinal tissue associated with the Alzheimer’s disease. We imaged the retina of wild-type (WT) and transgenic mouse model (TMM) of Alzheimer’s disease with optical coherence tomography and classify retinas into the WT and TMM groups using support vector machines with the radial basis function kernel. Predictions reached an accuracy over 80% at the age of 4 months and over 90% at the age of 8 months. Texture analysis of computed fundus reference images suggests a more heterogeneous organization of the retina in transgenic mice at the age of 8 months in comparison to controls.This study was supported by the Neuroscience Mantero Belard Prize 2015 (Santa Casa da Misericórdia)(MB-1049-2015), by The Portuguese Foundation for Science and Technology (PEst-UID/NEU/04539/2013), by FEDER-COMPETE (POCI-01-0145-FEDER-007440) and Centro 2020 Regional Operational Programme (CENTRO-01-0145-FEDER-000008: BrainHealth 2020).info:eu-repo/semantics/publishedVersio

Relacionamentos de coopetição : tensões no setor de turismo em Portugal

Mestrado em MarketingNum mercado globalizado e cada vez mais competitivo as empresas enfrentam frequentemente novos desafios. As estratégias de coopetição são adotadas para fazer face a estes desafios, isto é, as empresas estabelecem relacionamentos empresariais que envolvem simultaneamente cooperação e competição. Não obstante, numa estratégia de coopetição surgem diversos tipos de tensões. A presente investigação tem como objetivo estudar o desenvolvimento do relacionamento de coopetição. Em particular, esta investigação pretende estudar as tensões existentes entre empresas envolvidas em relacionamentos coopetitivos e em que fases do desenvolvimento do relacionamento é que as mesmas ocorrem. Recorre-se ao método qualitativo, de caráter exploratório, com uma estratégia de estudo de caso. Os dois estudos de casos no setor de turismo - as Embarcações do Sado e os Tuk-Tuks de Lisboa - exploram dois serviços distintos, mas relacionados. Os casos são principalmente suportados por 10 entrevistas semiestruturadas em profundidade, presenciais ou via telefónica, aos sócios gerentes das empresas. A análise dos casos permite uma melhor compreensão desta temática, como o surgimento das tensões num relacionamento de coopetição e os tipos de tensões existentes em cada fase do desenvolvimento do relacionamento de coopetição. Em suma, a presente investigação permitiu concluir que num relacionamento de coopetição é possível criar valor, quando existem estratégias e objetivos comuns. Contudo, as empresas devem conciliar os objetivos mútuos com os objetivos privados. Diversas tensões surgem ao longo do relacionamento coopetitivo condicionando o seu desenvolvimento.In a globalized and increasingly competitive market, companies often face new challenges. Coopetition strategies are adopted to address these challenges, which means companies establish business relationships that involve both cooperation and competition. Nevertheless, there are several tension types that can arise from coopetition strategies. The present research aims to study the coopetition relationship´s development. Specifically, this research aims to study the existing tensions between companies involved in coopetitive relationships and the stages of relationship development in which they occur. This study uses the qualitative method of exploratory character and follows a case study strategy. The two case studies are in the touristic sector - the Sado Vessels and the Lisbon Tuk-Tuks - and explore two separate but related services. The cases are mainly supported by 10 in-depth semi-structured interviews, either in person and by telephone, conducted with the managing partners of the companies. The case analysis opens room to a better understanding of this theme, such as the emergence of tensions in a coopetition relationship and the existing tension types in each phase of the coopetition relationship`s development. In summary, the present investigation concludes that, in a coopetition relationship, creating value is possible where there are common strategies and goals. However, companies must synchronize their mutual goals with their private ones. Several tensions arise throughout the coopetitive relationship and condition its development.info:eu-repo/semantics/publishedVersio

Phenomenology and cosmological constraints on f(Q) gravity

Tese de Mestrado, Física (Astrofísica e Cosmologia), 2022, Universidade de Lisboa, Faculdade de CiênciasThe late-time accelerated expansion of the Universe has been a challenge for modern Cosmology since its detection. General Relativity explains this phenomenon via the introduction of the cosmological constant, Λ. This what is known as the standard cosmological model or ΛCDM. However, the cosmological constant solution brings a series of shortcomings that have guided cosmologists to explore and propose alternative models to describe the late-time cosmic acceler ation. These proposed alternatives have ranged from models of a dynamical dark fluid, known as Dark Energy, to long-scale modifications of the gravitational interaction, known as Modified Gravity models. Inside the Modified Gravity approach, one can construct theories of gravity built from the scalars associated with non-metricity (Q). The latter is the symmetric teleparallel description which has been shown to be equivalent to General Relativity. Nonetheless, its gener alisation with a general function of the non-metricity, f(Q), has generated symmetric teleparallel theories of gravity with exciting properties beyond the standard cosmological scenario. This dissertation aims to analyse the viability of f(Q) gravity theories as a challenging model for ΛCDM. We focus on the analysis of two forms of the f(Q) function: one which only changes the cosmological perturbations at large linear scale compared to ΛCDM and a second one which introduces a modification in both the background expansion history and in linear perturbations. We explore both the background phenomenology of the models and their impact on the cosmological observables. To this purpose, we adapt an Einstein-Boltzmann code, dubbed MGCAMB, by implementing these models. We then provide for the first time cosmological constraints by using Markov chain Monte Carlo methods and large sets of data spanning from measurements of the background expansion of the Universe to those of gravitational potentials, matter density and temperature fluctuations of the Cosmic Microwave Background radiation. We conclude our investigation with a model selection analysis using χ 2 statistics and deviance information criteria. They will inform us whether the f(Q) models analysed are supported by data over the ΛCDM scenario. In this analysis we identify specific features in the temperature-temperature power spectrum, matter power spectrum and lensing power spectrum which make the f(Q) model distinguishable from the ΛCDM scenario. Finally from the model selection analysis, we find that the f(Q) gravity models can show, in some cases, a better fit to current data than the standard model. The capability of suppressing large-scale temperature anisotropies is the main sources of a better agreement with data

The fair value of employee stock options : Nestlé’s case study

The issuance of IFRS 2 – Share-based payment, in 2004, raised several criticisms, mostly related with one specific type of share-based payment transaction – employee stock options (ESO). The mandatory recognition and disclosure of its fair value impacted not only profitability, but also a corporate governance related issue – executives’ remuneration. Given the specificities of this particular type of call options, entities are faced with some difficulties in applying option pricing models to its valuation, but are also faced with opportunities to exercise managerial discretion over the model inputs. This thesis analyses and comments IFRS 2 guidelines in detail, supported by existing literature. It also applies the guidelines provided by this standard to a specific case study – Nestlé’s employee stock options granted in 2011 - to truly understand the difficulties and opportunities that an entity faces when estimating fair value of ESO. After providing 28 valid alternative valuations for the same ESO grant, we conclude that, in 2011, Nestlé apparently understated the amount expensed with regard to the ESO granted, possibly due to opportunistic motivations to reduce the perceived executives’ remuneration and to increase the perceived entity’s profitability. To finalise, we provide recommendations on additional disclosures, which would improve the transparency and quality of the information provided by the financial statements

Fixos da saúde e fluxos na difusão e atendimento de pacientes com Covid-19 em São Luís, Maranhão, Brasil

Este trabalho discute a dinâmica de difusão da Covid-19 no Maranhão a partir dos fluxos desencadeados durante a pandemia, por pessoas buscando atendimento em São Luís. Discute também a seletividade com que o território maranhense é usado por empresas de saúde, resultando em zonas de densidade, como São Luís, e zonas de rarefação, como a maior parte dos demais centros do estado. Na pandemia, essa particularidade regional gerou fluxos de pessoas em busca de diagnóstico e tratamento, ampliando áreas de contágio e fragilizando o sistema de saúde. Metodologicamente, o trabalho analisa a distribuição de equipamentos médico-hospitalares e de fixos da saúde para discutir a mobilidade de pessoas, agravada pela pandemia. Os dados advêm sobretudo do Sistema de Informações de Saúde e do Cadastro Nacional dos Estabelecimentos de Saúde do Brasil (ambos do Datasus, Ministério da Saúde) e da Secretaria de Estado da Saúde do Maranhão. Os resultados indicam que a Covid-19 intensificou fluxo de pessoas para São Luís, ampliando a área de contágio e o número de óbitos na capital.This work aims to discuss the dynamics of the spread of covid-19 in Maranhão from the flows triggered, during the pandemic, by people seeking care in São Luís. density, like São Luís, and rarefaction zones, like most of the other centers of the state. In the pandemic, this regional particularity generated flows of people in search of diagnosis and treatment, expanding areas of contagion and weakening the health system. Methodologically, the work analyzes the distribution of medical and hospital equipment and fixed health equipment to discuss the mobility of people, aggravated by the pandemic. The data come mainly from the Health Information System and the National Registry of Health Establishments in Brazil (both from Datasus, Ministry of Health) and from the State Department of Health of Maranhão.Este trabajo tiene como objetivo discutir la dinámica de propagación de Covid-19 en Maranhão a partir de los flujos desencadenados, durante la pandemia, por personas que buscan atención en São Luís: densidad, como São Luís, y zonas de rarefacción, como la mayoría de los otros centros de el estado. En la pandemia, esta particularidad regional generó flujos de personas en busca de diagnóstico y tratamiento, ampliando las áreas de contagio y debilitando el sistema de salud. Metodológicamente, el trabajo analiza la distribución de equipos médicos y hospitalarios y equipos fijos de salud para discutir la movilidad de las personas, agravada por la pandemia. Los datos provienen principalmente del Sistema de Información en Salud y del Registro Nacional de Establecimientos de Salud de Brasil (ambos del Datasus, Ministerio de Salud) y de la Secretaría de Estado de Salud de Maranhão. Los resultados indican que la Covid-19 intensificó el flujo de personas hacia São Luís, ampliando el área de contagio y el número de muertos en la capital

Major aproaches of the use of FRP and Bio-Oss® in bone regeneration and elevation for implantology: a concise systematic review

Introduction: In the scenario of maxillary sinus surgery for the later practice of implantology, several surgical techniques can be used to reconstruct the atrophic alveolar ridge, isolated techniques or associated with autogenous, allogeneic, xenogenous, and alloplastic biomaterials. The autogenous bone graft is the only one capable of presenting three important biological properties (osteogenesis, osteoinduction, and osteoconduction) guaranteeing a self-regenerative potential. Platelet concentrates have been proposed as regenerative materials in tissue regeneration procedures. Among the platelet concentrates proposed in the literature, there is FRP that act as autogenous platelet aggregates with osteoinductive properties. As an example of xenografts, Bio-Oss® stands out, being a bovine bone biomaterial. The excellent osteoconductive properties of Bio-Oss® lead to predictable and efficient bone regeneration, becoming an integral part of bone structure and volume. Objective: To carry out a brief systematic review of the main considerations for the use of fibrin-rich plasma and Bio Oss® in bone regeneration for implant dentistry. Methods: The survey was conducted from May 2021 to July 2021 and developed based on Scopus, PubMed, Science Direct, Scielo, and Google Scholar, following the rules of Systematic Review-PRISMA. Study quality was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results: The lack of bone in the alveolar crests has been a major problem in functional aesthetic recovery in patients who have suffered dentoalveolar trauma, traumatic tooth extractions, congenital tooth loss, maxillary and mandibular pathologies, in addition to infections due to the emotional and possibility of deformity. In this context, implant dentistry stands out as a modern method of oral rehabilitation for totally or partially edentulous patients. For this method to develop properly, bone integration of the implant into the recipient bone tissue must occur. It was documented that the combination of biomaterial and FRP significantly improved bone regeneration in the peri-implant area. Placing the implant with the simultaneous use of the FRP creates a good relationship between hard tissue and soft tissue. FRP is used as an adjuvant to Bio-Oss® particles for bone augmentation in the maxillary sinus. Conclusion: Based on literary findings, it was shown that FRP is favorable for bone formation processes for dental implants, especially when combined with Bio-Oss®

DETERMINAÇÃO E FICÇÃO NAS INVESTIGAÇÕES FILOSÓFICAS

resumo: As Investigações Filosóficas são apresentadas nesse artigo a partir de duas chaves, determinação e ficção. A determinação corresponde ao eixo de transformação de um pensamento que redefine a função de elementos normativos no interior de uma linguagem instituída fundamentalmente a partir de práticas. A ficção, por sua vez, consiste numa estratégia para fazer ver aquilo que está mais além do que nos permite enxergar a adesão incondicional (cegueira) aos nossos quadros normativos, sendo por isso uma estratégia tão fecunda quanto perturbadora. O artigo terá cumprido seu propósito se deixar a impressão de que este já antigo livro contém ainda sementes de muitos pensamentos imprescindíveis ao mundo do século XXI.   PALAVRAS-CHAVE: Wittgenstein. determinação. ficção. pragmática. Investigações Filosóficas.   ABSTRACT: Philosophical Investigations are presented in this article from two keys, determination and fiction. Determination corresponds to the axis of transformation of a thought that redefines the function of normative elements within a language fundamentally instituted from practices. Fiction, in turn, consists in a strategy to make us see beyond what the unconditional adherence (blindness) to our normative frameworks allows us to see, being therefore a strategy as fruitful as disturbing. The article will have served its purpose if it leaves the impression that this already old book still contains the seeds of many thoughts indispensable to the world of the 21st century. KEYWORDS: Wittgenstein. determination. fiction. pragmatic. Philosophical Investigation