Shear-induced lamellar phase of an ionic liquid crystal at room temperature

The phase behaviour of a number of N-alkylimidazolium salts was studied using polarizing optical microscopy, differential scanning calorimetry and X-ray diffraction. Two of these compounds exhibit lamellar mesophases at temperatures above 50 degrees C. In these systems, the liquid crystalline behaviour may be induced at room temperature by shear. Sheared films of these materials, observed between crossed polarisers, have a morphology that is typical of (wet) liquid foams: they partition into dark domains separated by brighter (birefringent) walls, which are approximately arcs of circle and meet at "Plateau borders" with three or more sides. Where walls meet three at a time, they do so at approximately 120 degrees angles. These patterns coarsen with time and both T1 and T2 processes have been observed, as in foams. The time evolution of domains is also consistent with von Neumann's law. We conjecture that the bright walls are regions of high concentration of defects produced by shear, and that the system is dominated by the interfacial tension between these walls and the uniform domains. The control of self-organised monodomains, as observed in these systems, is expected to play an important role in potential applications.

How foam-like is the shear-induced lamellar phase of an ionic liquid crystal?

Philosophical Magazine Letters Volume 88, Issue 9-10, 2008 Special Issue: Solid and Liquid Foams. In commemoration of Manuel Amaral Fortes

Media digitais e transformações na comunicação pública e científica

Este número especial da revista Estudos em Comunicação/Communication Studies é dedicado ao tema “Media digitais e transformações na comunicação pública e científica” e visa divulgar resultados do projecto “Mutação dos Media: Transformações da comunicação pública e científica” (PTDC/CCI-COM/100765/2008), financiado pela FCT com verbas do Orçamento de Estado e desenvolvido de Fevereiro de 2010 a Julho de 2013.

Transformations induced in bulk amorphous silica by ultrafast laser direct writingTransformations induced in bulk amorphous silica by ultrafast laser direct writing

Agências Financiadoras: Fundação para a Ciência e a Tecnologia - PTDC/FIS/102127/2008 e PTDC/FIS/102127/2008 e SFRH/BPD/78871/2011; Spanish Ministerio de Ciencia e Innovacion - FUNCOAT-CSD2008-00023-CONSOLIDER; Instituto Superior Técnico;

A cultura na primeira página: a relação entre media, agentes culturais e públicos

Os jornais não acompanham o movimento de descentralização cultural iniciado na última década do séc. XX e descuida a programação realizada nos equipamentos espalhados um pouco por todo o país e pelos diversos grupos artísticos e culturais a desenvolver o seu trabalho fora de Lisboa. Que estratégias têm seguido esses equipamentos para contornar esta situação, para ganhar visibilidade de outras formas. Sabendo que a imprensa tem um papel importante ao incitar à ação e em formar opiniões e atitudes sobre os assuntos, aposta-se na imprensa regional e em meios cuja produção e atualização depende das próprias estruturas, nomeadamente sites e presença nas redes sociais. No entanto, se se quer atrair visitantes de fora da região, a imprensa continua a conseguir fixar o interesse e trazer público, menor é o papel que desempenha junto dos residentes. Levar os residentes a participar é algo que passa por outras estratégias de comunicação que não a imprensa nacional, e é nessas estratégias que muitas vezes os responsáveis por estas estruturas se centram, desenvolvendo e promovendo outras fontes de experiência.

Revista Media e Jornalismo: Imagens e Jornalismo

Número dedicado à reflexão sobre o papel das imagens visuais no jornalismo contemporâneo. Os contributos dos diferentes autores aqui publicados permitem confirmar a importância de imagem como objeto de estudo, sobretudo no campo jornalístico, onde o seu potencial enquanto meio e linguagem continua a nortear as discussões.

Futuro dos media passa pelas marcas

Na Escola Superior de Comunicação Social (ESCS), em Lisboa, o jornalismo, a publicidade, o marketing e as relações públicas não estão em crise, É que, todos os anos, há sempre dez vezes mais candidatos do que vagas. Jorge Veríssimo, presidente da instituição, diz que a componente tecnológica e o ambiente profissional são o segredo de uma escola que tornou obrigatória uma cadeira de Empreendedorismo. Sobre o futuro dos media, diz oque passa cada vez mais por uma interligação entre jornalismo e marcas.

On the adaptation of broadcast transactions in token-passing fieldbus networks with heterogeneous transmission media

Broadcast networks that are characterised by having different physical layers (PhL) demand some kind of traffic adaptation between segments, in order to avoid traffic congestion in linking devices. In many LANs, this problem is solved by the actual linking devices, which use some kind of flow control mechanism that either tell transmitting stations to pause (the transmission) or just discard frames. In this paper, we address the case of token-passing fieldbus networks operating in a broadcast fashion and involving message transactions over heterogeneous (wired or wireless) physical layers. For the addressed case, real-time and reliability requirements demand a different solution to the traffic adaptation problem. Our approach relies on the insertion of an appropriate idle time before a station issuing a request frame. In this way, we guarantee that the linking devices’ queues do not increase in a way that the timeliness properties of the overall system turn out to be unsuitable for the targeted applications.

Ligand-Induced structural changes in TEM‑1 probed by molecular dynamics and relative binding free energy calculations

The TEM family of enzymes has had a crucial impact on the pharmaceutical industry due to their important role in antibiotic resistance. Even with the latest technologies in structural biology and genomics, no 3D structure of a TEM- 1/antibiotic complex is known previous to acylation. Therefore, the comprehension of their capability in acylate antibiotics is based on the protein macromolecular structure uncomplexed. In this work, molecular docking, molecular dynamic simulations, and relative free energy calculations were applied in order to get a comprehensive and thorough analysis of TEM-1/ampicillin and TEM-1/amoxicillin complexes. We described the complexes and analyzed the effect of ligand binding on the overall structure. We clearly demonstrate that the key residues involved in the stability of the ligand (hot-spots) vary with the nature of the ligand. Structural effects such as (i) the distances between interfacial residues (Ser70−Oγ and Lys73−Nζ, Lys73−Nζ and Ser130−Oγ, and Ser70−Oγ−Ser130−Oγ), (ii) side chain rotamer variation (Tyr105 and Glu240), and (iii) the presence of conserved waters can be also influenced by ligand binding. This study supports the hypothesis that TEM-1 suffers structural modifications upon ligand binding.

A proposal for media component brokerage

This paper describes how MPEG-4 object based video (obv) can be used to allow selected objects to be inserted into the play-out stream to a specific user based on a profile derived for that user. The application scenario described here is for personalized product placement, and considers the value of this application in the current and evolving commercial media distribution market given the huge emphasis media distributors are currently placing on targeted advertising. This level of application of video content requires a sophisticated content description and metadata system (e.g., MPEG-7). The scenario considers the requirement for global libraries to provide the objects to be inserted into the streams. The paper then considers the commercial trading of objects between the libraries, video service providers, advertising agencies and other parties involved in the service. Consequently a brokerage of video objects is proposed based on negotiation and trading using intelligent agents representing the various parties. The proposed Media Brokerage Platform is a multi-agent system structured in two layers. In the top layer, there is a collection of coarse grain agents representing the real world players – the providers and deliverers of media contents and the market regulator profiler – and, in the bottom layer, there is a set of finer grain agents constituting the marketplace – the delegate agents and the market agent. For knowledge representation (domain, strategic and negotiation protocols) we propose a Semantic Web approach based on ontologies. The media components contents should be represented in MPEG-7 and the metadata describing the objects to be traded should follow a specific ontology. The top layer content providers and deliverers are modelled by intelligent autonomous agents that express their will to transact – buy or sell – media components by registering at a service registry. The market regulator profiler creates, according to the selected profile, a market agent, which, in turn, checks the service registry for potential trading partners for a given component and invites them for the marketplace. The subsequent negotiation and actual transaction is performed by delegate agents in accordance with their profiles and the predefined rules of the market.

B2B platform for media content personalisation

This paper proposes a novel business model to support media content personalisation: an agent-based business-to-business (B2B) brokerage platform for media content producer and distributor businesses. Distributors aim to provide viewers with a personalised content experience and producers wish to en-sure that their media objects are watched by as many targeted viewers as possible. In this scenario viewers and media objects (main programmes and candidate objects for insertion) have profiles and, in the case of main programme objects, are annotated with placeholders representing personalisation opportunities, i.e., locations for insertion of personalised media objects. The MultiMedia Brokerage (MMB) platform is a multiagent multilayered brokerage composed by agents that act as sellers and buyers of viewer stream timeslots and/or media objects on behalf of the registered businesses. These agents engage in negotiations to select the media objects that best match the current programme and viewer profiles.

Campanha de comunicação de Ambient Media para a marca Leroy Merlin

Trabalho de projeto apresentado à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Publicidade e Marketing.

Experimental study of proton induced nuclear reactions in 6,7 Li

This work presents the results of the experimental study of proton induced nuclear reactions in lithium, namely the 7Li(p,α) 4He, 6Li(p,α) 3He and 7Li(p,p)7Li reactions. The amount of 7Li and 6Li identified as primordial and observed in very old stars of the Milky Way galactic halo strongly deviates from the predictions of primordial nucleosynthesis and stellar evolution models which depend, among other factors, on the cross sections of reactions like 7Li(p,α) 4He and 6Li(p,α) 3He. These discrepancies have triggered a large amount of research in the fields of stellar evolution, cosmology, pre-galactic evolution and low energy nuclear reactions. Focusing on nuclear reactions, this work has measured the 7Li(p,α) 4He and 6Li(p,α) 3He reactions cross sections (expressed in terms of the astrophysical S -factor) with higher accuracy, and the electron screening effects in these reactions for different environments (insulators and metallic targets). The 7Li(p,α) 4He angular distributions were also measured. These measurementstook place in two laboratory facilities, in the framework of the LUNA (Laboratory for Undergroud Nuclear Astrophysics) international collaboration, namely the Laboratorio ´ de Feixe de Ioes ˜ in ITN (Instituto Tecnologico ´ e Nuclear) Sacavem, ´ Portugal, and the Dynamitron-TandemLaboratorium in Ruhr-Universitat¨ Bochum, Germany. The ITN target chamber was modified to measure these nuclear reactions, with the design and construction of new components, the addition of one turbomolecular pump and a cold finger. The 7Li(p,α) 4He and 6Li(p,α) 3He reactions were measured concurrently with seven and four targets, respectively. These targets were produced in order to obtain adequate and stable lithium depth profiles. In metallic environments, the measured electron screening potential energies are much higher than the predictions of atomic-physics models. The Debye screening model applied to the metallic conduction electrons is able to explain these high values. It is a simple model, but also very robust. Concerning primordial nucleosynthesis and stellar evolution models, these results are very important as they show that laboratory measurements are well controlled, and the model inputs from these cross sections are therefore correct. In this work the 7Li(p,p)7Li differential cross section was also measured, which is useful to describe the 7Li(p,α) 4He entrance channel.

Para lá dos jornalistas: influencer relations, uma nova era de Media Relations

Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Gestão Estratégica das Relações Públicas.

As Guerras Mundiais e as mutações na teoria social da comunicação e dos media

Se a guerra é a continuação da política por outros meios, então certamente que nela a comunicação, em sentido lato, esteve sempre presente e desempenhou um papel chave. As guerras não implicam apenas a violência, mas também a persuasão, a contrainformação, o convencimento e o combate ideológico. Nas guerras modernas, os media têm sido um elemento fundamental para mobilizar nações moldadas por dinâmicas de desenraizamento e desterritorialização com vista a um esforço conjunto de apoio popular à ação bélica do Estado. Este artigo incide nas transformações que a própria teoria e investigação em comunicação e media sofreram no período entre as duas Guerras Mundiais do século XX. Trata-se de um contexto histórico decisivo para compreender como a institucionalização do campo da comunicação num país central como os EUA ocorreu em condições sociais e políticas que contribuíram para o seu perfil epistemológico, posições teóricas e para a configuração do poder no próprio sistema científico universitário, cujas repercussões continuam a fazer-se sentir de diversas e complexas formas.