Serial experiments lain's body: o corpo enquanto fronteira entre o físico e o virtual

Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Audiovisual e Multimédia.

Complex Dynamics of defective interfering baculoviruses during serial passage in insect cells

Defective interfering (DI) viruses are thought to cause oscillations in virus levels, known as the ‘Von Magnus effect’. Interference by DI viruses has been proposed to underlie these dynamics, although experimental tests of this idea have not been forthcoming. For the baculoviruses, insect viruses commonly used for the expression of heterologous proteins in insect cells, the molecular mechanisms underlying DI generation have been investigated. However, the dynamics of baculovirus populations harboring DIs have not been studied in detail. In order to address this issue, we used quantitative real-time PCR to determine the levels of helper and DI viruses during 50 serial passages of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) in Sf21 cells. Unexpectedly, the helper and DI viruses changed levels largely in phase, and oscillations were highly irregular, suggesting the presence of chaos. We therefore developed a simple mathematical model of baculovirus-DI dynamics. This theoretical model reproduced patterns qualitatively similar to the experimental data. Although we cannot exclude that experimental variation (noise) plays an important role in generating the observed patterns, the presence of chaos in the model dynamics was confirmed with the computation of the maximal Lyapunov exponent, and a Ruelle-Takens-Newhouse route to chaos was identified at decreasing production of DI viruses, using mutation as a control parameter. Our results contribute to a better understanding of the dynamics of DI baculoviruses, and suggest that changes in virus levels over passages may exhibit chaos.

Bias dependent photocurrent collection in p-i-n a-Si : EVSiC : H heterojunction

A series of large area single layers and heterojunction cells in the assembly glass/ZnO:Al/p (SixC1-x:H)/i (Si:H)/n (SixC1-x:H)/Al (0 serial resistances around 10(5)Ohm are also measured Simulated results confirm the experimental findings suggesting that the transport in dark depends almost exclusively on field-aided drift while under illumination it is dependent mainly on minority carriers the diffusion.

New Technique for Uniform Voltage Sharing in Series Stacked Semiconductors

This paper describes the operation of a solid-state series stacked topology used as a serial and parallel switch in pulsed power applications. The proposed circuit, developed from the Marx generator concept, balances the voltage stress on each series stacked semiconductor, distributing the total voltage evenly. Experimental results from a 10 kV laboratory series stacked switch, using 1200 V semiconductors in a ten stages solid-state series stacked circuit, are reported and discussed, considering resistive, capacitive and inductive type loads for high and low duty factor voltage pulse operation.

O metacinema norte-americano e o storytelling : de Orson Welles a David Lynch

ABSTRACT: The American metacinema which, by tradition, is narrative but extremely formulaic favours the story above the telling. No man contributed more to alter this state of affairs than Orson Welles, whose cinematic practice exalted the filmic enunciation and linked it more explicitly to the narrative intentions of the creator, making it obvious that metanarrative is synonymous with metacinema. With Citizen Kane (1941), in particular, the cinema was made more disnarrative, as meant by French writer/director Alain Robbe–Grillet, well ahead of Modernism. The fragmented narration, the temporal convolutions, a tendency for paradox and the interpretative obstacles all come together to anticipate the serial practice of David Lynch in his last four features. Structuring the films in segments which constitute different but complementary versions of the same events, Lynch manages to express the director’s enunciation along with the narration of the characters, reinforcing the role of the telling in the midst of the story. In INLAND EMPIRE (2006) the use of mise-en-abyme as a way of duplicating stories and tellers further increases the objective and complicates what is clearly the reign of the puzzle or mind-game film. In the footsteps of Welles, Lynch contributed for an outbreak of metanarrative / metacinematic crossover indie films closer to the European aesthetic practice but still very much within the American narrative tradition.

Sistema de multiprocessamento para simulação de N-corpos em FPGA

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia de Electrónica e Telecomunicações

O Estado no jornalismo “informativo”

A historiografia política que se debruça sobre o fim do regime monárquico refere, abundantemente, as ligações dos políticos e dos partidos aos jornais, no entanto, o jornalismo é assunto lateral e excêntrico da história política. Quando nos aproximamos dos estudos jornalísticos portugueses e procuramos compreender o comportamento dos jornais face ao político na viragem do século XIX temos de imediato uma grelha interpretativa acessível e dicotómica: em Portugal existiria uma imprensa de opinião, partidária, apaixonada, e uma outra informativa e apartidária. A esta última caberia a fórmula do sucesso. Esta abordagem do jornalismo, se têm a vantagem de nos chamar a atenção para a existência de várias práticas jornalísticas remete, porém, para um âmbito cronológico longo e vago ( “ século XIX”, “ último quartel do século XIX”) dizendo-nos pouco, sobre o objeto que enfatiza: o jornalismo informativo. Tende ainda a reproduzir as histórias institucionais dos jornais e as memórias dos profissionais do jornalismo, secundarizando a análise dos jornais. Nos escassos estudos jornalísticos sobre o período é forte a tendência para procurar encontrar e identificar no passado indícios dos vícios ou idealizações do jornalismo contemporâneo. Tanto mais que cronologicamente coincide o nosso estudo com o período (para alguns a “etapa” decisiva, ao ponto de lhe chamarem a ”idade de ouro da imprensa”) particularmente acarinhado por uma história “natural”do jornalismo, que aqui encontra a modernidade (leia-se autonomia face ao poder político, profissionalização do jornalista) “pela mão” da publicidade ( libertadora) fruto da industrialização oitocentista. A maior dificuldade para quem estuda os jornais da época contemporânea é o carácter gigantesco do acervo documental. O carácter serial dos periódicos, o seu ritmo diário, ao remeterem para rotinas, sugeriram-nos o presente trabalho: procurar surpreender o tratamento e organização da “ notícia” em nove jornais diários ( “ informativos” e de “opinião”) no dia 1 de Abril de 1906: no Século, Diário de Notícias, Mundo, Vanguarda, Luta, Popular, Opinião, Novidades e Diário Ilustrado. Nesse dia, os jornais informativos registavam com minúcia atos administrativos e rotinas burocráticas. Boa parte delas antecipavam a letra do Diário de Governo, outras, seguiam os trâmites legais dos processos coletivos e individuais que, por uma razão ou por outra, viajavam para nova instância administrativa à espera de decisão superior. E corria eficiente a máquina do Estado nas páginas do Século e no Diário de Notícias. Ministérios, secretarias, direções gerais, comissões, conselhos, etc., despachavam serviço. Parte do trabalho dos jornais informativos passava então por recolher e transcrever estas informações. Uma parcela significativa trabalho jornalístico era o puro registo, com pouco ou nenhum lugar para tratamento de edição, seja na seleção ou hierarquização dos factos noticiados, seja na contextualização dos atos administrativos editados. A reprodução integral das informações recolhidas junto da máquina do Estado dotava a “notícia” de uma linguagem técnico-burocrática que remetia para um rigor e racionalidade ausente, na concepção do próprio jornal, e verdadeiramente contrastante com o “ reflexo” caótico da sociedade que este dava a ler .

GPU implementation of a hyperspectral coded aperture algorithm for compressive sensing

This paper presents a new parallel implementation of a previously hyperspectral coded aperture (HYCA) algorithm for compressive sensing on graphics processing units (GPUs). HYCA method combines the ideas of spectral unmixing and compressive sensing exploiting the high spatial correlation that can be observed in the data and the generally low number of endmembers needed in order to explain the data. The proposed implementation exploits the GPU architecture at low level, thus taking full advantage of the computational power of GPUs using shared memory and coalesced accesses to memory. The proposed algorithm is evaluated not only in terms of reconstruction error but also in terms of computational performance using two different GPU architectures by NVIDIA: GeForce GTX 590 and GeForce GTX TITAN. Experimental results using real data reveals signficant speedups up with regards to serial implementation.

Parallel method for sparse semisupervised hyperspectral unmixing

Parallel hyperspectral unmixing problem is considered in this paper. A semisupervised approach is developed under the linear mixture model, where the abundance's physical constraints are taken into account. The proposed approach relies on the increasing availability of spectral libraries of materials measured on the ground instead of resorting to endmember extraction methods. Since Libraries are potentially very large and hyperspectral datasets are of high dimensionality a parallel implementation in a pixel-by-pixel fashion is derived to properly exploits the graphics processing units (GPU) architecture at low level, thus taking full advantage of the computational power of GPUs. Experimental results obtained for real hyperspectral datasets reveal significant speedup factors, up to 164 times, with regards to optimized serial implementation.

Parallel sparse unmixing of hyperspectral data

In this paper, a new parallel method for sparse spectral unmixing of remotely sensed hyperspectral data on commodity graphics processing units (GPUs) is presented. A semi-supervised approach is adopted, which relies on the increasing availability of spectral libraries of materials measured on the ground instead of resorting to endmember extraction methods. This method is based on the spectral unmixing by splitting and augmented Lagrangian (SUNSAL) that estimates the material's abundance fractions. The parallel method is performed in a pixel-by-pixel fashion and its implementation properly exploits the GPU architecture at low level, thus taking full advantage of the computational power of GPUs. Experimental results obtained for simulated and real hyperspectral datasets reveal significant speedup factors, up to 1 64 times, with regards to optimized serial implementation.