A NEW METHODOLOGY FOR STOCHASTIC SIMULATION OF DAILY CLIMATIC DATA PRESERVING THE INTERANNUAL VARIABILITY

In this work we propose a new methodology to reproduce, by means of simulations, the interannual variability of climatic variables which included only the minimum air temperature. To evaluate the performance of the proposed method, it was maked a comparison with other two weather generators (i.e., PGECLIMA_R and LARS-WG). Moreover, it was utilized the historical series of thirty years of five meteorological stations of the state of Parana - Brazil to generate ten sets of thirty years for each model, which were confronted with the respective historical series. The performance of the proposed model as well as weather generators was evaluated by applying tests of central tendency, variability and distribution. Furthermore, was utilized the statistical measures RMSE, MBE and Willmott agreement index (d). In the stations investigated, the proposed methodology reduced the total error and eliminated the negative bias of interannual variability. In only four (of 600) generated sequences the interannual variability differs significantly from the observed one. The series generated by PGECLIMA_R and LARS-WG presented rejection rate of 99% in the variability test. In this case, the bias was ten times greater and the RMSE was twice times greater than the proposed methodology. The d index was always greater than 0.98 for the five locations in the proposed methodology and around 0.83 in other models. Based on these results, the new methodology provides a relevant contribution concerning the interannual variability of climatic variables

The role of inflexible minorities in the breaking of democratic opinion dynamics

We study the effect of inflexible agents on two state opinion dynamics. The model operates via repeated local updates of random grouping of agents. While floater agents do eventually flip their opinion to follow the local majority, inflexible agents keep their opinion always unchanged. It is a quenched individual opinion. In the bare model (no inflexibles), a separator at 50% drives the dynamics towards either one of two pure attractors, each associated with a full polarization along one of the opinions. The initial majority wins. The existence of inflexibles for only one of the two opinions is found to shift the separator at a lower value than 50% in favor of that side. Moreover it creates an incompressible minority around the inflexibles, one of the pure attractors becoming a mixed phase attractor. In addition above a threshold of 17% inflexibles make their side sure of winning whatever the initial conditions are. The inflexible minority wins. An equal presence of inflexibles on both sides restores the balanced dynamics with again a separator at 50% and now two mixed phase attractors on each side. Nevertheless, beyond 25% the dynamics is reversed with a unique attractor at a fifty-fifty stable equilibrium. But a very small advantage in inflexibles results in a decisive lowering of the separator at the advantage of the corresponding opinion. A few percent advantage does guarantee to become majority with one single attractor. The model is solved exhaustedly for groups of size 3.Comment: 18 pages, 12 figure

A customisable pipeline for continuously harvesting socially-minded Twitter users

On social media platforms and Twitter in particular, specific classes of users such as influencers have been given satisfactory operational definitions in terms of network and content metrics. Others, for instance online activists, are not less important but their characterisation still requires experimenting. We make the hypothesis that such interesting users can be found within temporally and spatially localised contexts, i.e., small but topical fragments of the network containing interactions about social events or campaigns with a significant footprint on Twitter. To explore this hypothesis, we have designed a continuous user profile discovery pipeline that produces an ever-growing dataset of user profiles by harvesting and analysing contexts from the Twitter stream. The profiles dataset includes key network and content-based users metrics, enabling experimentation with user-defined score functions that characterise specific classes of online users. The paper describes the design and implementation of the pipeline and its empirical evaluation on a case study consisting of healthcare-related campaigns in the UK, showing how it supports the operational definitions of online activism, by comparing three experimental ranking functions. The code is publicly available.Comment: Procs. ICWE 2019, June 2019, Kore

Detection of HER2 from Haematoxylin-Eosin Slides Through a Cascade of Deep Learning Classifiers via Multi-Instance Learning

Breast cancer is the most frequently diagnosed cancer in woman. The correct identification of the HER2 receptor is a matter of major importance when dealing with breast cancer: an over-expression of HER2 is associated with aggressive clinical behaviour; moreover, HER2 targeted therapy results in a significant improvement in the overall survival rate. In this work, we employ a pipeline based on a cascade of deep neural network classifiers and multi-instance learning to detect the presence of HER2 from Haematoxylin–Eosin slides, which partly mimics the pathologist’s behaviour by first recognizing cancer and then evaluating HER2. Our results show that the proposed system presents a good overall effectiveness. Furthermore, the system design is prone to further improvements that can be easily deployed in order to increase the effectiveness score.Eduardo Conde-Sousa was supported by the project PPBI-POCI-01-0145-FEDER-022122, in the scope of Fundação para a Ciência e Tecnologia, Portugal (FCT) National Roadmap of Research Infrastructures

A Problemática da estratégia no sector das energias renováveis em Portugal

Dissertação apresentada ao Instituto Superior de Contabilidade e Administração do Porto para obtenção do Grau de Mestre em Gestão das Organizações, Ramo de Gestão de Empresas Orientada pelo Professor Doutor Eduardo Manuel Lopes de Sá e SilvaAs constantes mudanças a que a envolvente empresarial está sujeita leva a que o planeamento estratégico nos dias de hoje assuma-se como preponderante para o sucesso das organizações. Esta situação aplica-se de uma forma geral a todos os sectores, incluindo entre eles o sector das energias renováveis. A energia é imprescindível para o desenvolvimento das sociedades bem como para o seu progresso e crescimento. A crescente procura por energias renováveis prende-se com problemas actuais de sustentabilidade, ambientais, sociais e políticos, consequentes do consumo actual de combustíveis fósseis. No caso de Portugal além destes problemas enfrenta também um deficit energético. Assume as energias renováveis como uma solução total ou parcial para estes problemas. Verifica-se um crescimento forte da produção em Portugal com recurso a estas fontes, com maior incidência na região norte e sul. Os investimentos necessários neste sector variam substancialmente conforme o tipo de energia. Como abordagem empírica neste trabalho recorreu-se à entrevista procurando-se analisar e determinar a complexidade do planeamento estratégico e a forma como este é estruturado. De igual forma procurou-se aferir a forma de financiamento privilegiada

The influence on selectivity of the aluminum content in the matrix of FCC catalysts

The influence that both the type of matrix and the interaction between zeolite and matrix have on the selectivity of FCC catalysts was studied by means of the conversion of cyclohexene at 300 ◦C on a large number of samples in which the matrix was changed. Silica/alumina matrices had 0, 12 and 25% of alumina, and catalysts were subjected to steaming of varying severity followed by acid extraction in some samples to remove extraframework aluminum species (EFAl). Resulting  catalysts were characterized by various techniques. It was confirmed that hydrogen transfer does not depend directly on the type of coordination of the aluminum atoms in the sample, but rather on the density of paired sites in the zeolite component. It was possible to define the selectivity of reaction pathways (SRP) as an index to describe the relative importance of the processes ofdesorption via hydride transfer to yield cyclohexane against retention of the cation cyclohexil via isomerization and further reaction. A high value of SRP would mean that a given catalyst has a lower ability to retain adsorbed species that can be subjected to additional reactions like, in this particular reaction, isomerization and further proton transfer to the catalyst surface, or cracking. The index was shown to increase whereas the relative amount of octahedral aluminum atoms decreased, a fact that can be associated to the formation of a new silica/alumina phase. Such phase would be formed by means of the reaction of aluminum extracted from the zeolite upon steaming and silica present in the matrix.Fil: de la Puente, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Falabella Sousa Aguiar, Eduardo. Centro de Pesquisas-Petrobras; BrasilFil: Figueiredo Costa, Alexandre. Centro de Pesquisas-Petrobras; BrasilFil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin

Effects of mass media on opinion spreading in the Sznajd sociophysics model

In this work we consider the influence of mass media in the dynamics of the two-dimensional Sznajd model. This influence acts as an external field, and it is introduced in the model by means of a probability $p$ of the agents to follow the media opinion. We performed Monte Carlo simulations on square lattices with different sizes, and our numerical results suggest a change on the critical behavior of the model, with the absence of the usual phase transition for $p>\sim 0.18$. Another effect of the probability $p$ is to decrease the average relaxation times $\tau$, that are log-normally distributed, as in the standard model. In addition, the $\tau$ values depend on the lattice size $L$ in a power-law form, $\tau\sim L^{\alpha}$, where the power-law exponent depends on the probability $p$.Comment: 11 pages, 8 figures, to appear in Physica

Pulmonary alveolar proteinosis: a rare pulmonary toxicity of sirolimus.

Transpl Int. 2007 Mar;20(3):291-6. Pulmonary alveolar proteinosis: a rare pulmonary toxicity of sirolimus. Pedroso SL, Martins LS, Sousa S, Reis A, Dias L, Henriques AC, Sarmento AM, Cabrita A. Nephrology Department, Hospital Geral de Santo António, Porto, Portugal. [email protected] Abstract The aim of our paper is to describe an unusual pulmonary toxicity of sirolimus (SRL) in a kidney transplant recipient. We present a 34-year-old woman with a second renal transplantation, complicated with steroid-resistant acute rejection and chronic allograft dysfunction. Two years after initiating SRL, she presented complaints of progressive dyspnoea, nonproductive cough, chest pain and low-grade fever of 1 month duration. She had chronic allograft nephropathy and slight elevation of lactic dehydrogenase levels. After exclusion of common reasons of this condition, a computed tomography (CT) of the thorax and bronchoscopy was performed, revealing ground-glass opacification with polygonal shapes on CT and an opaque appearance with numerous macrophages on bronchoalveolar lavage. The alveolar macrophages stained positive by Periodic acid-Schiff. Diagnosis of pulmonary alveolar proteinosis (PAP) was made and drug-induced toxicity was suspected. SRL was withdrawn with marked improvement in the patients' clinical and radiological status. PAP resolved within 3 months without further therapy. PAP is a very rare complication of SRL therapy with only a few cases described. Withdrawal of SRL with conversion to another immunosuppressant seems to be an appropriate procedure in this condition. PMID: 17291222 [PubMed - indexed for MEDLIN

TRPV1 feed-forward sensitisation depends on COX2 upregulation in primary sensory neurons

Increased activity and excitability (sensitisation) of a series of molecules including the transient receptor potential ion channel, vanilloid subfamily, member 1 (TRPV1) in pain-sensing (nociceptive) primary sensory neurons are pivotal for developing pathological pain experiences in tissue injuries. TRPV1 sensitisation is induced and maintained by two major mechanisms; post-translational and transcriptional changes in TRPV1 induced by inflammatory mediators produced and accumulated in injured tissues, and TRPV1 activation-induced feed-forward signalling. The latter mechanism includes synthesis of TRPV1 agonists within minutes, and upregulation of various receptors functionally linked to TRPV1 within a few hours, in nociceptive primary sensory neurons. Here, we report that a novel mechanism, which contributes to TRPV1 activation-induced TRPV1-sensitisation within ~ 30 min in at least ~ 30% of TRPV1-expressing cultured murine primary sensory neurons, is mediated through upregulation in cyclooxygenase 2 (COX2) expression and increased synthesis of a series of COX2 products. These findings highlight the importance of feed-forward signalling in sensitisation, and the value of inhibiting COX2 activity to control pain, in nociceptive primary sensory neurons in tissue injuries