Regularization of energy-momentum tensor correlators and parity-odd terms

We discuss the problem of regularizing correlators in conformal field theories. The only way to do it in coordinate space is to interpret them as distributions. Unfortunately except for the simplest cases we do not have tabulated mathematical results. The way out we pursue here is to go to momentum space and use Feynman diagram techniques and their regularization methods. We focus on the energy-momentum tensor correlators and, to gain insight, we compute and regularize 2-point functions in 2d with various techniques both in coordinate space and in momentum space, obtaining the same results. Then we do the same for 2-point functions in 4d. Finally we turn to 3-point function in 4d, and concentrate on the parity-odd part. We derive in particular the regularized trace and divergence of the energy-momentum tensor in a chiral fermion model. We discuss the problems related to the parity-odd trace anomaly.Comment: 40 pages, 1 figure. v2: minor changes and typos correcte

Rhythm and Structure: Brecht’s Antigone in performance

Brecht’s adaptation of Sophocles’ Antigone in 1948 was openly a political gesture that aspired to the complete rationalization of Greek Tragedy. From the beginning, Brecht made it his task to wrench ancient tragic poetry out of its “ideological haze”, and proceeded to dismantle and eliminate what he named the “element of fate”, the crucial substance of tragic myth itself. However, his encounter with Hölderlin's unorthodox translation of Antigone, the main source for his appropriation and rewriting of the play, led him to engage in a radical experiment in theatrical practice. From the isolated first performance of Antigone, a model was created – the Antigonemodell – that demanded a direct confrontation with the many obstacles brought about by the foreign structure of Greek tragedy as a whole. In turn, such difficulties brought to light the problem of rhythm in its relation to Brecht’s own ideas of how to perform ancient poetry in a modern setting, as exemplified by the originally alienating figure of the tragic chorus. More importantly, such obstacles put into question his ideas of performance in general, as well as the way they can still resonate in our own understanding of what performance is or might be in a broader sense

BEYOND SUSTAINABILITY – BIOPHILIC AND REGENERATIVE DESIGN IN ARCHITECTURE

The environment friendly design movement emerges from the clear view that human conventional action is destroying the living systems that support life on earth as we know it. This review paper underlines the limits of Sustainable concept and looks at Biophilia and Regenerative Design, two emerging concepts that appear to have a more appropriate answer to the environmental problems that we face today and in the future. This paper will give an overview of each concept and design framework, trying to interpret the way they operate, the differences, similarities and goals

Requoting the arcades. Walter Benjamin’s idle robbers

By contrasting Walter Benjamin’s fragmentary theory of quotation to the different ways his work has itself undergone quotation thus far, a new insight can be gained into the perception of the materiality and visuality of texts. The so-called Passagen-Werk, the project on the Parisian Arcades which Benjamin pursued for more than ten years until the end of his life, is the overflowing, yet voided space where this crossing takes place

Impact of social economic indicators on RSI incidence and success

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and EconomicsIn this project we study the influence of socio-economic characteristics on the percentage of beneficiaries of “Rendimento Social de Inserção” (RSI) and on the percentage of exits from the RSI program that occur due to a change in income. The results indicate that the % of beneficiaries tend to increase with unemployment, younger people and reduced families, whereas it tends to reduce with high education levels and GDP. As for the % of exists from the RSI, the results we obtained show evidence that, on the one hand, they tend to increase with higher education, and on the other hand, they tend to reduce with unemployment, reduced income of the beneficiaries before entering the program, nuclear families and Local Purchasing Power

The Infancy of the Esports Industry as a Risk to its Sponsors

In less than 10 years, esports have turned into a global phenomenon with a large following that rivals the audience size of popular established sports. This has resulted in a massive influx of esports sponsors. However, because it appeared and evolved so rapidly, sponsors have no idea of what esports really are nor of what risks they may face. Ergo, this research aimed to determine what issues are being caused by the infancy of the esports industry that is threatening sponsors. Hence, this exploratory research used a convergent-parallel mixed method with equal status. Empirical data was obtained through interviews with 22 experts in esports sponsoring and the application of a survey to 5,638 esports fans. Quantitative data was analysed with SPSS 25 and qualitative data with NVIVO 10. The results showed that the majority of experts considered that the problems associated with the infancy of the esports industry are a risk to esports sponsors and almost all esports fans reckon that the competitive gaming market has infancy-related issues to solve. Esports are not like general sports, so sponsors must holistically study this industry to mitigate the dangers of suffering from the problems of this new and unknown market

Helicopter flight modeling and robust autonomous control with uncertain dynamics

Helicopter flight control has gained greater visibility in the last decades due to its characteristics. It is a task of high difficulty due to the system being changeable. Helicopter control is the junction of several variables such as the flying qualities and performance, skill of the pilot, weather conditions, etc. For a given configuration of a helicopter (military, civil, SAR, etc.), we need precise control parameters, and is in flying qualities that we focus our attention. This paper is then dedicated to autonomous modeling and control of conventional rotarywing platforms, so that there is a good balance between robustness and performance of the system, so that when there are disturbances, it can stabilize more quickly and effectively and, to verify this, a particular helicopter is used for the validation of the methods elaborated: DRA research ZD559 Lynx (Lynx Mk7), still serving the UK Army Air Corps. In helicopter flight dynamics, will be focused autorotation phase and different flight speed phase and two specific control systems will be compared: normal LQR and robust LQR. Is then designed the controllers previously mentioned, comparing their results through the dynamic model already linearized in order to verify which one is most appropriate for the platform. When there is a change in the balance of the aircraft, it can return to the same position as quickly as possible. By the obtained results, it’s verified in both cases, success in stabilizing the aircraft and controlling it’s trajectory given different reference speeds, a controller is most evident than the other.O controlo de helicópteros tem vindo a adquirir nas últimas décadas maior visibilidade devido à característica desta aeronave. É uma tarefa de elevada dificuldade devido ao próprio sistema ser, já por si, inconstante. O controlo de helicópteros é a junção de várias variáveis como as qualidades de voo e performance, a perícia do piloto, condições atmosféricas, etc. Seja qual for a missão do helicóptero (militar, civil, SAR, etc), precisaremos de parâmetros de controlo precisos, e é nas qualidades de voo que iremos focar a nossa atenção. O presente trabalho é dedicado então à modelação e controlo autónomo de plataformas de asa rotativa convencional, de forma a que haja uma boa relação entre robustez e performance do sistema para que, quando hajam perturbações, o sistema possa estabilizar eficazmente e, para se verificar isso mesmo, um helicóptero específico é utilizado para a validação dos métodos elaborados: DRA research Lynx ZD559 (Lynx Mk7), ainda ao serviço do UK Army Air Corps. Na dinâmica do voo do helicóptero, irá ser focada a fase de autorrotação e fase de voo para diferentes velocidades e dois sistemas de controlo irão ser comparados: LQR normal e LQR robusto. Projectou-se então os controladores referidos anteriormente comparando os seus resultados através da dinâmica e navegação do modelo já linearizado, para se verificar qual dos dois será mais apropriado para que a plataforma, no momento em que existe uma alteração na dinâmica da aeronave, possa regressar a essa mesma posição o mais brevemente possivel. Através então dos resultados obtidos, verifica-se em ambos os casos, o sucesso em estabilizar a aeronave e controlar o voo dada uma determinada referência para diferentes velocidades, mas um controlador evidencia-se mais que o outro

Como Realizar Videos em Cirurgia Dermatológica: Uma Técnica de Gravação Simples e Barata

Video recording surgical procedures is one of the most valuable tools for teaching and self-assessment in Dermatologic Surgery. A number of recording systems have been described in the literature. Nevertheless, they’re usually expensive (~500€) and time-consuming to prepare, the latter being a major disadvantage for a busy surgical speciality such as Dermatology. The authors describe a simple and inexpensive technique for surgical video capture in Dermatologic Surgery. For this setup, the surgeon needs only a smartphone with a camera (which is nowadays ubiquitous), a bike phone holder (10€ to 30€), an adjustable intravenous pole and, optionally, a powerbank. With the patient in position for the surgical intervention (seated or lying on his back on the surgical table, depending on the procedure), the bike phone holder should be attached to the vertically adjustable intravenous pole. The smartphone must be then set on the bike phone holder, with its “recording mode” already started. Optionally, a powerbank can also be attached to the intravenous pole to provide extra charge for longer procedures. The height of the intravenous pole, as well as its position and distance to the surgical table, should be adjusted accordingly before the intervention, in order to provide the best recording definition. The authors describe a simple, easy to setup, inexpensive system to record videos in Dermatologic Surgery.A gravação vídeo de cirurgias ou de outros procedimentos dermatológicos é uma valiosa ferramenta de ensino e de autocritica. Alguns sistemas de gravação têm sido descritos na literatura, contudo estes habitualmente envolvem processos de montagem complexos e morosos que desincentivam à sua preparação, para além de dispendiosos em equipamento (500€ ou mais) ou pouco práticos pela logística que envolvem. Os autores descrevem uma técnica simples, de rápida preparação pré-operatória que faz recurso somente a equipamentos atualmente ubíquos na sociedade (smartphones com câmara) ou acessíveis em preço (<10€). Para a elaboração deste sistema são necessários um smartphone com câmara de vídeo, um suporte ajustável de telemóvel para bicicleta (STBicl) e, opcionalmente, uma powerbank (bateria portátil para carregamento de telemóveis ou outros equipamentos eletrónicos). Já com o doente em posição para a intervenção (exemplo: deitado na marquesa cirúrgica), o cirurgião dermatológico deverá colocar num suporte de soro o STBicl, em zona que possibilite o ajuste vertical. Já com o telemóvel em modo de vídeo, devidamente ajustado no STBicl, o cirurgião deverá regular a altura do suporte de soro e distância ao campo cirúrgico de modo a possibilitar a melhor definição sobre o local a intervencionar. Uma powerbank pode ser fixa ao suporte de soro para estender a bateria do telemóvel em procedimentos mais prolongados. Os autores demonstram uma técnica simples e económica para gravação vídeo de procedimentos dermatológicos

Price linkages in pharmaceutical markets

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and EconomicsThis paper studies the existing price linkage between generics and branded pharmaceuticals, in which the generic price must be a fraction of the latter. Using a vertical differentiation model, we look at the market equilibrium, the effects on the incentives for the brand producer to develop new products, and the possibility of predation by the brand producer over the generic firm. We find that the price linkage increases prices compared to no indexation and it may increase the incentives for the brand producer to expand its set of products. When prices are freely set, the branded firm may also want to expand a new product with a higher quality, but will prefer to remove the original one from the market. Predation may equally occur in both schemes but the price linkage may give fewer incentives for the branded firm to predate while compensating losses with a new drug

Extraction of opinionated profiles from comments on web news

Tese de mestrado integrado. Engenharia Informática e Computação. Faculdade de Engenharia. Universidade do Porto. 201