Immunohistochemistry in formalin-gel fixed tissues

There are several hazards in histopathology laboratories and its staff must ensure that their professional activity is set to the highest standards while complying with the best safety procedures. Formalin is one of the chemical hazards to which such professionals are routinely exposed. To decrease this contact, it is suggested that 10% neutral buffered liquid formalin (FL) is replaced by 10% formalin-gel (FG), given the later reduces the likelihood of spills and splashes, and decreased fume levels are released during its handling, proving itself less harmful. However, it is mandatory to assess the effectiveness of FG as a fixative and ensure that the subsequent complementary techniques, such as immunohistochemistry (IHC), are not compromised. Two groups of 30 samples from human placenta have been fixed with FG and FL fixatives during different periods of time (12, 24, and 48 hours) and, thereafter, processed, embedded, and sectioned. IHC for six different antibodies was performed and the results were scored (0–100) using an algorithm that took into account immunostaining intensity, percentage of staining structures, non-specific immunostaining, contrast, and morphological preservation. Parametric and non-parametric statistical tests were used (alpha = 0•05). All results were similar for both fixatives, with global score means of 95•36±6•65 for FL and 96•06±5•80 for FG, and without any statistical difference (P>0•05). The duration of the fixation had no statistical relevance also (P>0•05). So it is proved here FG could be an effective alternative to FL.

The Sticky Information Macro Model: Beyond Perfect Foresight

Sticky information monetary models have been used in the macroeconomic literature to explain some of the observed features regarding inflation dynamics. In this paper, we explore the consequences of relaxing the rational expectations assumption usually taken in this type of model; in particular, by considering expectations formed through adaptive learning, it is possible to arrive to results other than the trivial convergence to a fixed point long-term equilibrium. The results involve the possibility of endogenous cyclical motion (periodic and a-periodic), which emerges essentially in scenarios of hyperinflation. In low inflation settings, the introduction of learning implies a less severe impact of monetary shocks that, nevertheless, tend to last for additional time periods relative to the pure perfect foresight setup.

On the Suitability of Suffix Arrays for Lempel-Ziv Data Compression

Lossless compression algorithms of the Lempel-Ziv (LZ) family are widely used nowadays. Regarding time and memory requirements, LZ encoding is much more demanding than decoding. In order to speed up the encoding process, efficient data structures, like suffix trees, have been used. In this paper, we explore the use of suffix arrays to hold the dictionary of the LZ encoder, and propose an algorithm to search over it. We show that the resulting encoder attains roughly the same compression ratios as those based on suffix trees. However, the amount of memory required by the suffix array is fixed, and much lower than the variable amount of memory used by encoders based on suffix trees (which depends on the text to encode). We conclude that suffix arrays, when compared to suffix trees in terms of the trade-off among time, memory, and compression ratio, may be preferable in scenarios (e.g., embedded systems) where memory is at a premium and high speed is not critical.

Constructing good deals in discrete time arbitrage-free dynamic pricing models

Recent literature has proved that many classical pricing models (Black and Scholes, Heston, etc.) and risk measures (V aR, CV aR, etc.) may lead to “pathological meaningless situations”, since traders can build sequences of portfolios whose risk leveltends to −infinity and whose expected return tends to +infinity, i.e., (risk = −infinity, return = +infinity). Such a sequence of strategies may be called “good deal”. This paper focuses on the risk measures V aR and CV aR and analyzes this caveat in a discrete time complete pricing model. Under quite general conditions the explicit expression of a good deal is given, and its sensitivity with respect to some possible measurement errors is provided too. We point out that a critical property is the absence of short sales. In such a case we first construct a “shadow riskless asset” (SRA) without short sales and then the good deal is given by borrowing more and more money so as to invest in the SRA. It is also shown that the SRA is interested by itself, even if there are short selling restrictions.

Controlo de tráfego

O crescente número de automóveis nas ruas das grandes cidades, assim como o crescente número de transportes urbanos para atender o crescimento das populações, veio fazer com que as cidades cada vez mais fiquem mais congestionadas e mais propícias para acidentes envolvendo viaturas e peões. Devido a isso, foram criados sistemas de controlo de tráfego capazes de melhorar o tráfego urbano nas cidades, sem deixar de lado as preocupações com os peões e nem com as emissões de poluentes para o ar. Baseado nesse cenário, este trabalho tem como objetivo abordar as possíveis soluções existentes no mercado para melhorar o fluxo das viaturas, principalmente dos transportes colectivos, com prioridades para viaturas de emergências e autocarros, assim como, as passagens de peões, e sistemas de mobilidade urbana. Desempenho do transporte público pode ser melhorado através de um melhor controlo e gerenciamento de tráfego em geral. Nos testes realizados em campo: foi medida a velocidade de viagem do autocarro no cruzamento fixo (Praça de Espanha), e correlacionando-os com intervalos do ciclo dos semáforos para este cruzamento. A flexibilidade do controlador actuando, com o auxílio de detectores de veículos, sendo capaz de variar os intervalos dentro do ciclo, bem como o volume de carros e de prestações em velocidade de viagem do autocarro. Resultados mostram que, durante o período em estudo, os benefícios de velocidade da viagem do autocarro, seria possível, através de um verdadeiro controlo de tempo feedback de cooperação entre as áreas urbanas de controlo de tráfego (Gertrude) e do sistema de localização de veículos de transportes públicos (SAEIP). Ao longo prazo, sugerimos a implantação de um sistema integrado. Fazendo com que o volume no carro seja reduzido. Este efeito leva também, a um aumento da velocidade comercial do autocarro urbano, da mesma forma como foi proposto em nossa experiência.

Impact of maritime air mass trajectories on the Western European coast urban aerosol

Lisbon is the largest urban area in the Western European coast. Due to this geographical position the Atlantic Ocean serves as an important source of particles and plays an important role in many atmospheric processes. The main objectives of this study were to (1) perform a chemical characterization of particulate matter (PM2.5) sampled in Lisbon, (2) identify the main sources of particles, (3) determine PM contribution to this urban area, and (4) assess the impact of maritime air mass trajectories on concentration and composition of respirable PM sampled in Lisbon. During 2007, PM2.5 was collected on a daily basis in the center of Lisbon with a Partisol sampler. The exposed Teflon filters were measured by gravimetry and cut into two parts: one for analysis by instrumental neutron activation analysis (INAA) and the other by ion chromatography (IC). Principal component analysis (PCA) and multilinear regression analysis (MLRA) were used to identify possible sources of PM2.5 and determine mass contribution. Five main groups of sources were identified: secondary aerosols, traffic, calcium, soil, and sea. Four-day backtracking trajectories ending in Lisbon at the starting sampling time were calculated using the HYSPLIT model. Results showed that maritime transport scenarios were frequent. These episodes were characterized by a significant decrease of anthropogenic aerosol concentrations and exerted a significant role on air quality in this urban area.

Real-time rheology of actively growing bacteria

The population growth of a Staphylococcus aureus culture, an active colloidal system of spherical cells, was followed by rheological measurements, under steady-state and oscillatory shear flows. We observed a rich viscoelastic behavior as a consequence of the bacteria activity, namely, of their multiplication and density-dependent aggregation properties. In the early stages of growth (lag and exponential phases), the viscosity increases by about a factor of 20, presenting several drops and full recoveries. This allows us to evoke the existence of a percolation phenomenon. Remarkably, as the bacteria reach their late phase of development, in which the population stabilizes, the viscosity returns close to its initial value. Most probably, this is caused by a change in the bacteria physiological activity and in particular, by the decrease of their adhesion properties. The viscous and elastic moduli exhibit power-law behaviors compatible with the "soft glassy materials" model, whose exponents are dependent on the bacteria growth stage. DOI: 10.1103/PhysRevE.87.030701.

Public relations in part-time : full-time service: estratégia de comunicação para o lançamento de um novo modelo de negócio ds relações públicas em Portugal

O presente trabalho visa propor uma estratégia para a construção e lançamento de um novo modelo de negócio para a atuação das Relações Públicas em Portugal, numa proposta direcionada para as micro e pequenas empresas. Entre o serviço in house e a consultadoria clássica existe um espaço não coberto em Portugal: um serviço in house partilhado. Apresenta-se aqui este projeto de serviço de Relações Públicas para aqueles para quem é incomportável assumir nos seus quadros um Técnico de Comunicação.

A SON Enhanced Algorithm for Observed Time Differences Based Geolocation in Real 3G Networks

Conferência - 16th International Symposium on Wireless Personal Multimedia Communications (WPMC)- Jun 24-27, 2013

Efeito dos parâmetros técnicos na dose e qualidade de imagem num sistema de radiografia computorizada

Mestrado em Radiações Aplicadas às Tecnologias da Saúde - Ramo de especialização: Imagem Digital com Radiação X

The organ verses of Frei Jerónimo da Madre de Deus: Portuguese organ music in the time of D. João V

Contrastando com o importante legado dos mestres organistas portugueses dos séculos XVI e XVII, a música portuguesa para órgão pós-1700 parece quase inexistente (excluindo raros exemplos, como as quatro sonatas para órgão de Carlos Seixas). Seja devido à destruição causada pelo grande terramoto de Lisboa em 1755, ou a outras causas, a ausência de fontes é surpreendente, considerando os testemunhos de actividade musical durante aquele período. Este artigo lida com uma fonte até hoje relativamente ignorada: o manuscrito CLI/1-4 nº 7 da Biblioteca do Palácio Ducal de Vila Viçosa (Versos / Sobre o Canto Chão / Para Orgão / De Fr. Jeronimo da M.dre de DS.). Esta colecção de vinte versos para órgão de Jerónimo da Madre de Deus é, de longe, a maior obra portuguesa para órgão da primeira metade do século XVIII até hoje conhecida. Claramente pensadas para o órgão, estas curtas peças testemunham a transformação da escrita para tecla em Portugal durante o reinado de D. João V (nomeadamente através da absorção de influências italianas) e fornecem informações preciosas sobre o tipo de instrumento em que eram tocadas.

Implementação em hardware reconfigurável de método de separação de dados hiperespetrais

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

Sistema de reconhecimento de impressões digitais baseado em FPGA

Trabalho de Projeto para obtenção do grau de Mestre em Engenharia de Eletrónica e Telecomunicações

Avaliação de fiabilidade de sistemas elétricos e de automação em instalações de frio industrial

Dissertação para a obtenção do grau de Mestre em Engenharia Electrotécnica Ramo de Energia/Automação e Eletrónica Industrial

Power Producers Trading Electricity in Both Pool and Forward Markets

The electricity industry throughout the world, which has long been dominated by vertically integrated utilities, has experienced major changes. Deregulation, unbundling, wholesale and retail wheeling, and real-time pricing were abstract concepts a few years ago. Today market forces drive the price of electricity and reduce the net cost through increased competition. As power markets continue to evolve, there is a growing need for advanced modeling approaches. This article addresses the challenge of maximizing the profit (or return) of power producers through the optimization of their share of customers. Power producers have fixed production marginal costs and decide the quantity of energy to sell in both day-ahead markets and a set of target clients, by negotiating bilateral contracts involving a three-rate tariff. Producers sell energy by considering the prices of a reference week and five different types of clients with specific load profiles. They analyze several tariffs and determine the best share of customers, i.e., the share that maximizes profit. © 2014 IEEE.