Oceanic interchange and nonequilibrium population structure in the estuarine dependent Indo-Pacific tasselfish, Polynemus sheridani

We assayed mtDNA haplotype [300 base pairs (bp) control region] geography and genealogy in the Indo-Pacific tasselfish, Polynemus sheridani from its contiguous estuarine distribution across northern Australia (n = 169). Eight estuaries were sampled from three oceanographic regions (Timor Sea, Gulf of Carpentaria and the Coral Sea) to assess the impact of Pleistocene sea level changes on the historical connectivity among P. sheridani populations. Specifically, we investigated the genetic consequences of disruption to Indian-Pacific Ocean connectivity brought about by the closure of the Torres Strait. Overall there was significant population subdivision among estuaries (F-ST = 0.161, (Phi(ST) = 0.187). Despite a linear distribution, P. sheridani did not show isolation by distance over the entire sampled range because of genetic similarity of estuaries greater than 3000 km apart. However, significant isolation by distance was detected between estuaries separated by less than 3000 km of coastline. Unlike many genetic studies of Indo-Pacific marine species, there was no evidence for an historical division between eastern and western populations. Instead, phylogeographical patterns were dominated by a starlike intraspecific phylogeny coupled with evidence for population expansion in both the Gulf of Carpentaria and the Coral Sea but not the Timor Sea. This was interpreted as evidence for recent west to east recolonization across of northern Australia following the last postglacial marine advance. We argue that although sufficient time has elapsed postcolonization for populations to approach gene flow-drift equilibrium over smaller spatial scales (< 3000 km), the signal of historical colonization persists to obscure the expected equilibrium pattern of isolation by distance over large spatial scales (> 3000 km).

Stratigraphy, facies architecture and tectonic implications of the Upper Devonian to Lower Carboniferous Campwyn Volcanics of the northern New England Fold Belt

Upper Devonian to Lower Carboniferous strata of the Campwyn Volcanics of east central Queensland preserve a substantial sequence of first-cycle volcaniclastic sedimentary and coeval volcanic rocks that record prolonged volcanic activity along the northern New England Fold Belt. The style and scale of volcanism varied with time, producing an Upper Devonian sequence of mafic volcano-sedimentary rocks overlain by a rhyolitic ignimbrite-dominated sequence that passes upward into a Lower Carboniferous limestone-bearing sedimentary sequence. We define two facies associations for the Campwyn Volcanics. A lower facies association is dominated by mafic volcanic-derived sedimentary breccias with subordinate primary mafic volcanic rocks comprising predominantly hyaloclastite and peperite. Sedimentary breccias record episodic and high energy, subaqueous depositional events with clastic material sourced from a mafic lava-dominated terrain. Some breccias contain a high proportion of attenuated dense, glassy mafic juvenile clasts, suggesting a syn-eruptive origin. The lower facies association coarsens upwards from a lithic sand-dominated sequence through a thick interval of pebble- to boulder-grade polymict volcaniclastic breccias, culminating in facies that demonstrate subaerial exposure. The silicic upper facies association marks a significant change in eruptive style, magma composition and the nature of eruptive sources, as well as the widespread development of subaerial depositional conditions. Crystal-rich, high-grade, low- to high-silica rhyolite ignimbrites dominate the base of this facies association. Biostratigraphic age controls indicate that the ignimbrite-bearing sequences are Famennian to lower-mid Tournaisian in age. The ignimbrites represent extra-caldera facies with individual units up to 40 m thick and mostly lacking coarse lithic breccias. Thick deposits of pyroclastic material interbedded with fine-grained siliceous sandstone and mudstone (locally radiolarian-bearing) were deposited from pyroclastic flows that crossed palaeoshorelines or represent syn-eruptive, resedimented pyroclastic material. Some block-bearing lithic-pumice-crystal breccias may also reflect more proximal subaqueous silicic explosive eruptions. Crystal-lithic sandstones interbedded with, and overlying the ignimbrites, contain abundant detrital volcanic quartz and feldspar derived from the pyroclastic deposits. Limestone is common in the upper part of the upper facies association, and several beds are oolitic (cf. Rockhampton Group of the Yarrol terrane). Overall, the upper facies association fines upward and is transgressive, recording a return to shallow-marine conditions. Palaeocurrent data from all stratigraphic levels in the Campwyn Volcanics indicate that the regional sediment-dispersal direction was to the northwest, and opposed to the generally accepted notion of easterly sediment dispersal from a volcanic arc source. The silicic upper facies association correlates in age and lithology to Early Carboniferous silicic volcanism in the Drummond (Cycle 1) and Burdekin Basins, Connors Arch, and in the Yarrol terranes of eastern Queensland. The widespread development of silicic volcanism in the Early Carboniferous indicates that silicic (rift-related) magmatism was not restricted to the Drummond Basin, but was part of a more substantial silicic igneous province.

Impact of commercial fishing on Trindade Island and Martin Vaz Archipelago, Brazil : characteristics, conservation status of the species involved and prospects for preservation

Reportamos atividades de pesca comerciais no complexo insular mais afastado da costa brasileira: Ilha da Trindade e Arquipélago Martin Vaz. As atividades foram estudadas através de embarques e entrevistas com os mestres e pescadores das embarcações durante uma expedição cientifica realizada entre fevereiro e abril de 2007. Quatro modalidades de atividades de pesca são realizadas na região, capturando ao menos sete espécies que possuem algum risco de extinção. O estabelecimento de normas específicas de restrição para atividades que pescam sobre os recifes das ilhas é uma alternativa para a conservação das espécies ameaçadas. O monitoramento das embarcações pode ocorrer via satélite através do programa nacional de rastreamento de embarcações pesqueiras (PREPS).

Fatores relacionados à cronologia de erupção da dentição decídua

O objetivo deste estudo foi estimar a cronologia e sequência de erupção da dentição decídua e seus fatores relacionados em amostra de crianças de duas regiões do município de Vitória, ES. Os dados utilizados no estudo são provenientes de um estudo longitudinal realizado entre 2003 e 2006 com 86 recém-nascidos que foram acompanhados até a idade de 36 meses de vida, cuja coleta de dados foi obtida por meio da aplicação de um formulário as mães e da realização de um exame clínico nas crianças. Um total de 67 crianças permaneceram até o final do estudo. Calculou-se a idade média de erupção dos dentes decíduos de cada criança e foram aplicados o teste de kappa, McNemar e kappa ajustado pela prevalência. Em seguida realizou-se a Análise de Sobrevivência. Os resultados mostraram que a média de erupção dos dentes decíduos variou de oito a 29 meses de vida no arco inferior, e de 11 a 30 meses no arco superior e que os maiores níveis de concordância foram para os tempos de erupção dos incisivos e caninos decíduos (71/81, kappa = 0,82; IC95% = 0,72-0,93; 53/63, kappa = 0,76; IC95% = 0,62-0,88) do que para os molares decíduos. Dos fatores relacionados a cronologia de erupção da dentição decídua, foi identificado na Regressão de Cox que os hábitos alimentares infantis podem influenciar, acelerando e retardando esse processo eruptivo. Recomenda-se o conhecimento do perfil de erupção decídua de cada população para que tais evidências sirvam de base para a implementação de medidas de prevenção e controle da saúde dessa população e auxilie na elaboração de estratégias, com ações de proteção e promoção da saúde. As ações tem como finalidade a prevenção de possíveis alterações bucais e gerais durante o crescimento e desenvolvimento infantil e melhoria da qualidade de vida dessa população.

An Electromagnetic Tracker System for the design of a dental superstructure

Nowadays, different techniques are available for manufacturing full-arch implant-supported prosthesis, many of them based on an impression procedure. Nevertheless, the long-term success of the prosthesis is highly influenced by the accuracy during such process, being affected by factors such as the impression material, implant position, angulation and depth. This paper investigates the feasibility of a 3D electromagnetic motion tracking system as an acquisition method for modeling such prosthesis. To this extent, we propose an implant acquisition method at the patient mouth, using a specific prototyped tool coupled with a tracker sensor, and a set of calibration procedures (for distortion correction and tool calibration), that ultimately obtains combined measurements of the implant’s position and angulation, and eliminating the use of any impression material. However, in the particular case of the evaluated tracking system, the order of magnitude of the obtained errors invalidates its use for this specific application.

Electromagnetic tracker feasibility in the design of a dental superstructure for edentulous patients

The success of the osseointegration concept and the Brånemark protocol is highly associated to the accuracy in the production of an implant-supported prosthesis. One of most critical steps for long-term success of these prosthesis is the accuracy obtained during the impression procedure, which is affected by factors such as the impression material, implant position, angulation and depth. This paper investigates the feasibility of 3D electromagnetic motion tracking systems as an acquisition method for modeling full-arch implant-supported prosthesis. To this extent, we propose an implant acquisition method at the patient mouth and a calibration procedure, based on a 3D electromagnetic tracker that obtains combined measurements of implant’s position and angulation, eliminating the use of any impression material. Three calibration algorithms (namely linear interpolation, higher-order polynomial and Hardy multiquadric) were tested to compensate for the electromagnetic tracker distortions introduced by the presence of nearby metals. Moreover, implants from different suppliers were also tested to study its impact on tracking accuracy. The calibration methodology and the algorithms employed proved to implement a suitable strategy for the evaluation of novel dental impression techniques. However, in the particular case of the evaluated electromagnetic tracking system, the order of magnitude of the obtained errors invalidates its use for the full-arch modeling of implant-supported prosthesis.

The importance of quality of life in patients with multiple sclerosis: do they need auxiliary walking devices?

Objective: To describe the importance of training multiple sclerosis (MS) patients with auxiliary walking devices (walking stick, crutch, or wheelchair) in a way that achieves a better quality of life (QOL). Design: Exploratory and descriptive. Setting: General hospital in Portugal.

Concessão Douro Litoral A32/IC2: passagens inferiores pré-fabricadas no sistema arco "Techspan" e muros ala de suporte de terras no sistema "Terra Armada": ponte sobre o rio Antuã: aplicação da tecnologia "Freyssinet"

O presente relatório visa apresentar o trabalho desenvolvido pelo estagiário na empresa Freyssinet – Terra Armada, S.A. (FTA). O relatório traduz o acompanhamento do estagiário na construção e aplicação da tecnologia Terra Armada em duas passagens inferiores, bem como o acompanhamento dos trabalhos efectuados pela empresa FTA no que diz respeito à aplicação da tecnologia Freyssinet na ponte sobre o rio Antuã, estando ambas as obras abordadas inseridas no Lote 8 – “A32/IC2 Oliveira de Azeméis/IP1 (S. Lourenço) trecho 2 e 3 – a cargo da empresa Alves Ribeiro S.A.. Com a construção dos trechos 2 e 3 da A32 surgiu a necessidade de se restabelecerem algumas ligações, o que fez com que após estudadas as soluções passíveis de serem utilizadas, se tivesse optado pela construção de túneis a céu aberto na execução dos restabelecimentos. Descreve-se neste documento a metodologia utilizada e as tecnologias patenteadas pela empresa Terra Armada, sendo estas compostas pelos Arcos “Techspan” e muros de ala executados com recurso à tecnologia “Terra Armada”. Em relação à ponte sobre o rio Antuã inserida no trecho 2 da empreitada de construção da A32, foi construída com recurso a cimbre auto-lançável e betonada in situ, havendo a necessidade de aplicação de tecnologias patenteadas pela Freyssinet no que diz respeito às actividades de pré-esforço, aparelhos de apoio nas ligações entre o tabuleiro e os pilares e juntas de dilatação na ligação do tabuleiro aos encontros. Apresentam-se os procedimentos de montagem e aplicação das tecnologias anteriormente referidas. No presente relatório estão descritos e explicados detalhadamente os trabalhos executados pela FTA, nomeadamente a aplicação da tecnologia “Terra Armada” no que diz respeito à construção das passagens inferiores, e a aplicação da tecnologia “Freyssinet” aplicada aquando da construção da ponte sobre o rio Antuã.

Volatility regimes for the VIX index

This article presents a Markov chain framework to characterize the behavior of the CBOE Volatility Index (VIX index). Two possible regimes are considered: high volatility and low volatility. The specification accounts for deviations from normality and the existence of persistence in the evolution of the VIX index. Since the time evolution of the VIX index seems to indicate that its conditional variance is not constant over time, I consider two different versions of the model. In the first one, the variance of the index is a function of the volatility regime, whereas the second version includes an autoregressive conditional heteroskedasticity (ARCH) specification for the conditional variance of the index.

YouTubers as satirists: humour and remix in online video

This article aims to discuss the role humour plays in politics, particularly in a media environment overflowing with user-generated video. We start with a genealogy of political satire, from classical to Internet times, followed by a general description of “the Downfall meme,” a series of videos on YouTube featuring footage from the film Der Untergang and nonsensical subtitles. Amid video-games, celebrities, and the Internet itself, politicians and politics are the target of such twenty-first century caricatures. By analysing these videos we hope to elucidate how the manipulation of images is embedded in everyday practices and may be of political consequence, namely by deflating politicians' constructed media image. The realm of image, at the centre of the Internet's technological culture, is connected with decisive aspects of today's social structure of knowledge and play. It is timely to understand which part of “playing” is in fact an expressive practice with political significance.

Towards an efficient and robust foot classification from pedobarographic images

O documento em anexo encontra-se na versão post-print (versão corrigida pelo editor).

Assimetria na volatilidade dos mercados de acções

Mestrado em Controlo e Gestão dos Negócios

Análise de clusters e volatilidade de índices de acções

Mestrado em Contabilidade e Gestão das Instituições Financeiras

The histopathological approach to inflammatory bowel disease: a practice guide

Inflammatory bowel diseases (IBDs) are lifelong disorders predominantly present in developed countries. In their pathogenesis, an interaction between genetic and environmental factors is involved. This practice guide, prepared on behalf of the European Society of Pathology and the European Crohn's and Colitis Organisation, intends to provide a thorough basis for the histological evaluation of resection specimens and biopsy samples from patients with ulcerative colitis or Crohn's disease. Histopathologically, these diseases are characterised by the extent and the distribution of mucosal architectural abnormality, the cellularity of the lamina propria and the cell types present, but these features frequently overlap. If a definitive diagnosis is not possible, the term indeterminate colitis is used for resection specimens and the term inflammatory bowel disease unclassified for biopsies. Activity of disease is reflected by neutrophil granulocyte infiltration and epithelial damage. The evolution of the histological features that are useful for diagnosis is time- and disease-activity dependent: early disease and long-standing disease show different microscopic aspects. Likewise, the histopathology of childhood-onset IBD is distinctly different from adult-onset IBD. In the differential diagnosis of severe colitis refractory to immunosuppressive therapy, reactivation of latent cytomegalovirus (CMV) infection should be considered and CMV should be tested for in all patients. Finally, patients with longstanding IBD have an increased risk for the development of adenocarcinoma. Dysplasia is the universally used marker of an increased cancer risk, but inter-observer agreement is poor for the categories low-grade dysplasia and indefinite for dysplasia. A diagnosis of dysplasia should not be made by a single pathologist but needs to be confirmed by a pathologist with expertise in gastrointestinal pathology.

Weaving encounters: towards an art of participation

In the early 21st Century, with the phenomenon of digital convergence, the consecration of Web 2.0, the decrease of the cost of cameras and video recorders, the proliferation of mobile phones, laptops and wireless technologies, we witness the arising of a new wave of media, of an informal, personal and at times “minority” nature, facilitating social networks, a culture of fans, of sharing and remix. As digital networks become fully and deeply intricate in our experience, the idea of “participation” arises as one of the most complex and controversial themes of the contemporary critical discourse, namely in what concerns contemporary art and new media art. However, the idea of “participation” as a practice or postulate traverses the 20th century art playing an essential role in its auto-critic, in questioning the concept of author, and in the dilution of the frontiers between art, “life” and society, emphasizing the process, the everyday and a community sense. As such, questioning the new media art in light of a “participatory art” (Frieling, 2008) invokes a double gaze simultaneously attentive to the emerging figures of a “participatory aesthetics” in digital arts and of the genealogy in which it is included. In fact, relating the new media art with the complex and paradoxical phenomenon of “participation” allows us to, on the one hand, avoid “digital formalism” (Lovink, 2008) and analyse the relations between digital art and contemporary social movements; on the other hand, this angle of analysis contributes to reinforce the dialogue and the links between digital art and contemporary art, questioning the alleged frontiers that separate them.