Permanence in polymatrix replicators

Generally a biological system is said to be permanent if under small perturbations none of the species goes to extinction. In 1979 P.Schuster, K.Sigmund, and R.Wolff introduced the concept of permanence as a stability notion for systems that models the self-organization of biological macromolecules. After, in 1987 W. Jansen, and J.Hofbauer, and K.Sigmund give sufficient conditions for permanence in the usual replicators. In this paper we extend these results for polymatrix replicators.info:eu-repo/semantics/publishedVersio

Coconut water and BAP successfully replaced zeatin in olive (Olea europaea L.) micropropagation

The data presented report on trials conducted during 24 months using the Portuguese olive cultivar ‘Galega vulgar’. The effectiveness of coconut water, BAP, or kinetin, as possible zeatin substitutes in olive micropropagation protocols, was investigated. In all stages of the micropropagation process, the mineral and vitamin formulation of Olive Medium (OM) was used. Regarding culture establishment the best results were achieved when 50 ml l-1 coconut water and 2.22 µM BAP were used as medium supplements. For the in vitro multiplication stage, the highest proliferation rates with an average of 3.4 new explants on each thirty days were achieved maintaining the coconut water concentration at 50 ml l-1 and increasing BAP up to 8.87 µM. The effects of IBA and activated charcoal on the in vitro root induction were also studied. Rooting rates of over 85 percent were obtained by basal immersion of the explants in IBA solution at 3 g l-1 for 10 seconds, followed by inoculation in the OM culture medium, added with 2 g l-1 of activated charcoal and without growth regulators. All in vitro rooted plants were transferred into jiffy-pots filled with vermiculite-perlite 3/1 (v/v) substrate. Those were subsequently wetted with the OM mineral solution, placed into polystyrene plates each one with 100 jiffy-pots capacity, which were transferred to traditional rooting mist benches, on a water-cooling equipped greenhouse. Such a simple acclimatization procedure allowed for 95 percent of plants survival

Storytelling and social media as tools for brand recognition: The role of digital influencers

This dissertation’s main goal was to understand the effect storytelling and influencer marketing have on the consumers’ purchase intention, in a time when the connection between consumer and brand is extremely relevant. In recent times the internet came to change the way communication happens, these changes affected the advertising sector as much as any other. Giving the amount of information available online, the consumers’ profile changed too. People are searching for personalized information and brands that match their personal values. By using a quantitative methodology, surveys, this dissertation intends to evaluate Portuguese’s’ presence online as well as the ways in which they are affected by storytelling and influencer marketing. As a main conclusion it was possible to assess that Portuguese are affected by these marketing strategies, however, not in an evenly way. Age turned out to be an important factor to take in consideration.Esta dissertação teve como principal objetivo entender o efeito que o storytelling em conjunto com o marketing de influência têm na intensão de compra do consumidor, numa época em que a ligação entre este e a marca é um fator extremamente relevante. Nos dias de hoje em que a internet veio revolucionar a forma como a comunicação acontece, o setor da publicidade foi também afetado por essas mudanças. As pessoas passaram a procurar informação personalizada e a consumir marcas que correspondam aos seus valores pessoais. Recorrendo a uma metodologia quantitativa, por meio de inquéritos, esta dissertação pretende avaliar a presença dos portugueses online assim como a forma como estes são afetados pelo storytelling e pelo marketing de influência. Como principal conclusão é possível destacar o facto de que os portugueses são, sim, afetados por estas estratégias, no entanto, não de uma forma igual. A idade revelou-se, ao longo deste estudo, como um fator determinante

Pet sense: sistema de monitorização de animais em hospitalização

The observation and treatment of animals in veterinary hospitals is still very dependent on manual procedures, including the collection of vital signs (temperature, heart rate, respiratory rate and blood pressure). These manual procedures are time-consuming and invasive, affecting the animal’s well-being. In this work, we purpose the use of IoT technologies to monitor animals in hospitalization, wearing sensors to collect vitals, and low-cost hardware to forward them into a cloud backend that analyses and stores data. The history of observed vitals and alarms can be accessed in the web, included in the Pet Universal software suite. The overall architecture follows a stream processing approach, using telemetry protocols to transport data, and Apache Kafka Streams to analyse streams and trigger alarms on potential hazard conditions. The system was fully implemented, although with laboratory sensors to emulate the smart devices to be worn by the animals. We were able to implement a data gathering and processing pipeline and integrate with the existing clinical management information system. The proposed solution can offer a practical way for long-term monitoring and detect abnormal values of temperature and heart rate in hospitalized animals, taking into consideration the characteristics of the monitored individual (species and state).A observação e tratamento de animais hospitalizados continua muito dependente de procedimentos manuais, especialmente no que diz respeito à colheita de sinais vitais (temperatura, frequência cardíaca, frequência respiratória e pressão arterial). Estes procedimentos manuais são dispendiosos em termos de tempo e afetam o bem-estar do animal. Neste projeto, propomos o recurso a tecnologias IoT para monitorizar animais hospitalizados equipados com sensores que medem sinais vitais, com hardware acessível, e envio dos dados para um serviço na cloud que os analisa e armazena. O histórico dos valores e alarmes podem ser acedidos na web e incluídos na plataforma comercial da Pet Universal. A arquitetura geral segue uma abordagem de processamento funcional, usando protocolos de telemetria para transportar dados e Apache Kafka Streams, analisando e lançando alarmes sobre potenciais condições de risco de acordo com a temperatura e pulsação. O sistema foi totalmente implementado, embora com sensores de laboratório para simular os dispositivos a serem usados pelos animais. Conseguimos implementar um circuito de colheita e processamento de dados e integrar com o sistema de gestão clínica já existente. A solução proposta oferece uma forma prática de monitorização continuada e de deteção de valores anormais de temperatura e frequência cardíaca em animais hospitalizados, tomando em conta as características do indivíduo monitorado (espécie e estado).Mestrado em Engenharia Informátic

Periodic attractor in the discrete time best-response dynamics of the rock-paper-scissors game

The Rock-Paper-Scissors (RPS) game is a classic noncooperative game widely studied in terms of its theoretical analysis as well as in its applications, ranging from sociology and biology to economics. Many experimental results of the RPS game indicate that this game is better modelled by the discretized best-response dynamics rather than continuous time dynamics. In this work we show that the attractor of the discrete time best-response dynamics of the RPS game is nite and periodic. Moreover we also describe the bifurcations of the attractor and determine the exact number, period and location of the periodic strategies.info:eu-repo/semantics/publishedVersio

Lotka-volterra systems and polymatrix replicators

Tese de doutoramento, Matemática (Análise Matemática), Universidade de Lisboa, Faculdade de Ciências, 2015In the 1970’s John M. Smith and George R. Price [22] applied the theory of strategic games developed by John von Neumann and Oskar Morgenstern [42] in the 1940’s to investigate the dynamical processes of biological populations, giving rise to the field of the Evolutionary Game Theory (EGT). Some classes of ordinary differential equations (o.d.e.s) which plays a central role in EGT are the Lotka-Volterra systems (LV), the replicator equation, the bimatrix replicator and the polymatrix replicator. Many properties of the LV systems can be geometrically expressed in terms of its associated graph, constructed from the system’s interaction matrix. For the class of stably dissipative LV systems we prove that the rank of its defining matrix, which is the dimension of the associated invariant foliation, is completely determined by the system’s graph. In this thesis we also study analytic flows defined on polytopes. We present a theory that allows us to analyze the asymptotic dynamics of the flow along the heteroclinic network composed by the flowing-edges and the vertices of the polytope where the flow is defined. In this context, given a flow defined on a polytope, we give sufficient conditions for the existence of normally hyperbolic stable and unstable manifolds for heteroclinic cycles. In polymatrix games population is divided in a finite number of groups, each one with a finite number of strategies. Interactions between individuals of any two groups are allowed, including the same group. The differential equation associated to a polymatrix game, that we designate as polymatrix replicator, is defined in a polytope given by a finite product of simplices. Karl Sigmund and Josef Hofbauer [16] and Wolfgang Jansen [18] give sufficient conditions for permanence in the usual replicators. We generalize these results for polymatrix replicators. Also for polymatrix replicators we extend the concept of stably dissipativeness developed by Ray Redheffer et al. [25–29]. In this context we generalize a theorem of Waldyr Oliva et al. [6] about the Hamiltonian nature of the limit dynamics in “stably dissipative” polymatrix replicators. We present also some examples to illustrate fundamental results and concepts developed along the thesis.Na década de 1970 John M. Smith e George R. Price [22] começaram a usar a teoria de jogos estratégicos desenvolvida por John von Neumann e Oskar Morgenstern [42] nos anos 1940 para investigar os processos dinâmicos de populações, dando assim origem à Teoria de Jogos Evolutivos (TJE). Algumas classes de equações diferenciais ordinárias (e.d.o.s) que têm um papel central na TJE são os sistemas Lotka-Volterra (LV), a equação do replicador, o replicador bimatricial e o replicador polimatricial. Muitas propriedades dos sistemas LV podem ser expressas geometricamente em termos do seu grafo associado, construído a partir da matriz de interaçcão do sistema. Para a classe dos sistemas LV estavelmente dissipativos provamos que a característica da sua matriz de interaçcão, que é a dimensão da folheação invariante associada, é completamente determinada pelo grafo do sistema. Nesta tese estudamos também fluxos analíticos definidos em politopos. Apresentamos uma teoria que nos permite analisar a dinâmica assintótica do fluxo ao longo da rede heteroclítica formada pelas arestas e vértices do politopo onde os fluxos estão definidos. Neste contexto, dado um fluxo definido num politopo, damos condições suficientes para a existência de variedades normalmente hiperbólicas estáveis e instáveis para ciclos heteroclíticos. Nos jogos polimatriciais a população é dividida num número finito de grupos, cada um com um n´úmero finito de estratégias. As interaçcões entre indivíduos de quaisquer dois grupos podem ocorrer, inclusive do mesmo grupo. A equação diferencial associada a um jogo polimatricial, que designamos por replicador polimatricial, está definida num politopo dado por um produto finito de simplexos. Karl Sigmund e Josef Hofbauer [16] e Wolfgang Jansen [18] apresentam condições suficientes para a permanência nos replicadores usuais. Nesta tese generalizamos esses resultados para os jogos polimatriciais. Também para os replicadores polimatriciais estendemos o conceito de estabilidade dissipativa desenvolvido por Ray Redheffer et al. [25–29]. Neste contexto generalizamos um teorema de Waldyr Oliva et al. [6] sobre a natureza Hamiltoniana da dinâmica limite em replicadores polimatriciais “estavelmente dissipativos”. Apresentamos ainda alguns exemplos para ilustrar resultados e conceitos fundamentais desenvolvidos ao longo da tese.Fundo Social Europeu (FSE, Programa Operacional Potencial Humano - POPH

A Tale of Two Souths: microsatellite assessment of the role Portuguese Salmo salar populations play in Europe

Tese de mestrado, Biologia da Conservação, 2022, Universidade de Lisboa, Faculdade de CiênciasAtlantic salmon (Salmo salar L.) is an anadromous species with homing behaviour. Generally, individuals from this species are born in freshwater systems, migrate to feeding grounds in North Atlantic and return to their birthplace to reproduce. This reproductive isolation potentiates local adaptation. In recent years, Atlantic salmon populations in Europe have experienced great declines and are now classified as Vulnerable (VU). In Portugal, very little is known about this species, but this species is classified as Critically Endangered (CR), the highest threatened status. In this work, 14 microsatellite loci are used to assess population structure, migratory patterns and genetic diversity of 28 already identified and analysed populations (Gilbey et al., 2018), plus two additional populations, one from Galicia, Spain (Lerez River) and the other from Portuguese Minho basin (Mouro River). This is the first work to analyse Portuguese Atlantic salmon population’s genetics. The goal of the present study was to assess if the Portuguese populations were genetically distinguishable from other European populations. This work described a new Iberian genetic cluster, which is pointed out by several analysis (namely, STRUCTURE, PCoA and POPTREE2). This new group has a similar degree of differentiation from the Main European clusters as the Icelandic cluster that was described in previous works. Another important discovery described was the high relatedness among populations from Portugal and Galicia, when compared with the Asturian population, all located in the Iberian Peninsula. The genetic diversity analysis showed that the genetic uniqueness of each population is decreasing if compared to other works. The estimates of population effective size (Ne) indicate low Ne in most of the populations. It concludes that future genetic approaches to this species must consider this new Iberian cluster. On the other side, more studies must be done to fully understand the correlation between Iberian populations (in particular, northwestern coast populations and northern coast populations). It is also highlighted the necessity of management measures, for Portuguese populations since they are the most threatened populations

On the roots of underdevelopment : “wrong equilibrium” or “miscoordination”?

This paper examines the Big Push industrialization model due to [Murphy et al., 1989] by featuring a game where public and private agents must coordinate their complementary investment decisions and the outcome where all agents invest dominates in payoffs the no-investment alternative. Two different paths of analysis are pursued. If the coordination game has complete information, the selection of the “right” equilibrium appears to be easier if the initial level of total factor productivity (TFP) is not too low. The comparison of the “payoff dominance” and the “risk dominance” criteria due to [Harsanyi and Selten, 1988] shows that the ability to plan jointly different kinds of investment relaxes the constraint on initial TFP. Industrialization can be alternatively modelled as an incomplete information game. In this case, underdevelopment follows from a coordination break, where typically the Government supplies infrastructures which remain underused because the private sector fails to modernize. We find out that such a coordination break is likelier in economies where the starting level of TFP is low. Consequently, a low initial TFP level tends to create a “Poverty Trap”, which however can be overcome by enhancing the ability to coordinate different kinds of investment, namely public and private.info:eu-repo/semantics/publishedVersio