A new perspective for robustness assessment of framed structures

Robustness has been recognized as interesting research topic due to several collapses that have been occurring over last years. Indeed, this subject is related with global failure or collapse. However, its definition is not consensual since several definitions have been proposed in the literature. This shortpaper aims to present a framework for assessing bridge’s robustness as a probabilistic performance indicator. In this study, a non-linear model of a clamped beam with two point loads using DIANA software was developed to validate the framework presented. By means of a probabilistic approach, the load carrying capacity and structural safety were evaluated. In this regard, special focus is placed on an adaptive Monte Carlo simulation procedure to achieve a proper meta-model.ISISE – Institute for Sustainability and Innovation in Structural Engineering (PEstC/ECI/UI4029/2011 FCOM-01-0124-FEDER-022681)FCT– Portuguese Scientific Foundation for the research grant PD/BD/113677/2015European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement No. 60622

Alinhamento de vocabulário de domínio utilizando os sistemas AML e LogMap

Introduction: In the context of the Semantic Web, interoperability among heterogeneous ontologies is a challenge due to several factors, among which semantic ambiguity and redundancy stand out. To overcome these challenges, systems and algorithms are adopted to align different ontologies. In this study, it is understood that controlled vocabularies are a particular form of ontology. Objective: to obtain a vocabulary resulting from the alignment and fusion of the Vocabularies Scientific Domains and Scientific Areas of the Foundation for Science and Technology, - FCT, European Science Vocabulary - EuroSciVoc and United Nations Educational, Scientific and Cultural Organization - UNESCO nomenclature for fields of Science and Technology, in the Computing Sciences domain, to be used in the IViSSEM project. Methodology: literature review on systems/algorithms for ontology alignment, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses - PRISMA methodology; alignment of the three vocabularies; and validation of the resulting vocabulary by means of a Delphi study. Results: we proceeded to analyze the 25 ontology alignment systems and variants that participated in at least one track of the Ontology Alignment Evaluation Initiative competition between 2018 and 2019. From these systems, Agreement Maker Light and Log Map were selected to perform the alignment of the three vocabularies, making a cut to the area of Computer Science. Conclusion: The vocabulary was obtained from Agreement Maker Light for having presented a better performance. At the end, a vocabulary with 98 terms was obtained in the Computer Science domain to be adopted by the IViSSEM project. The alignment resulted from the vocabularies used by FCT (Portugal), with the one adopted by the European Union (EuroSciVoc) and another one from the domain of Science & Technology (UNESCO). This result is beneficial to other universities and projects, as well as to FCT itself.Introdução: No contexto da Web Semântica, a interoperabilidade entre ontologias heterogêneas é um desafio devido a diversos fatores entre os quais se destacam a ambiguidade e a redundância semântica. Para superar tais desafios, adota-se sistemas e algoritmos para alinhamento de diferentes ontologias. Neste estudo, entende-se que vocabulários controlados são uma forma particular de ontologias. Objetivo: obter um vocabulário resultante do alinhamento e fusão dos vocabulários Domínios Científicos e Áreas Científicas da Fundação para Ciência e Tecnologia, - FCT, European Science Vocabulary - EuroSciVoc e Organização das Nações Unidas para a Educação, a Ciência e a Cultura - UNESCO nomenclature for fields of Science and Technology, no domínio Ciências da Computação, para ser usado no âmbito do projeto IViSSEM. Metodologia: revisão da literatura sobre sistemas/algoritmos para alinhamento de ontologias, utilizando a metodologia Preferred Reporting Items for Systematic Reviews and Meta-Analyses - PRISMA; alinhamento dos três vocabulários; e validação do vocabulário resultante por meio do estudo Delphi. Resultados: procedeu-se à análise dos 25 sistemas de alinhamento de ontologias e variantes que participaram de pelo menos uma track da competição Ontology Alignment Evaluation Iniciative entre 2018 e 2019. Destes sistemas foram selecionados Agreement Maker Light e LogMap para realizar o alinhamento dos três vocabulários, fazendo um recorte para a área da Ciência da Computação. Conclusão: O vocabulário foi obtido a partir do Agreement Maker Light por ter apresentado uma melhor performance. Ao final foi obtido o vocabulário, com 98 termos, no domínio da Ciência da Computação a ser adotado pelo projeto IViSSEM. O alinhamento resultou dos vocabulários utilizados pela FCT (Portugal), com o adotado pela União Europeia (EuroSciVoc) e outro do domínio da Ciência&Tecnologia (UNESCO). Esse resultado é proveitoso para outras universidades e projetos, bem como para a própria FCT

Contrasting styles of Bi mineralization – equilibrium and evolution in Zambézia Pegmatite Province, Mozambique

O cariz generalizado da ocorrência de minerais de bismuto na Província Pegmatítica da Zambézia deverá expressar uma especialização protolítica bismutífera primordial que foi sequencialmente mobilisada pela instalação e evolução dos magmas granito-pegmatíticos correspondentes aos campos de Melatube, Naípa e Namacotche. Evoluções magmáticas a hidrotermais distintas e o alcance da interacção água-rocha, dependente da maior ou menor abertura dos sistemas, explicam os contrastes paragenéticos observados.Widespread occurrence of Bi minerals in Zambézia Pegmatite Province must represent a protolithic Bi - specialisation mobilised by the emplacement and evolution of Melatube, Naípa and Namacotche granitepegmatite magmas. Distinct magmatic to hydrothermal evolutions and extend of water-rock interaction, in contrasting conditions of close or open system, explain the observed paragenetical variability

Bi-Ti-Nb-Ta fractionation in granitic pegmatites as a paragenetic guide for aquamarine detection: Melatube case study (Mocuba, Mozambique)

A assinatura geoquímica dos minerais de Nb-Ta-Ti e a sua associação com minerais de bismuto no grupo pegmatítico de Melatube, põe em evidência algumas condições de intrusão e cristalização favoráveis à formação de água-marinha, na transição, zona intermédia - núcleo de quartzo: a) presença de rochas meta-ultrabásicas encaixantes; b) espessura adequada do corpo pegmatítico; c) dissipação lenta de calor permitindo forte difusão de constituintes, nucleação viável e crescimento regular.The geochemical signature of Nb-Ta-Ti – group minerals and associated Bi phases in Melatube pegmatites emphasizes the importance of some specific genetic conditions controlling aquamarine crystallisation at the transition between intermediate zone and quartz core: a) presence of meta-ultrabasic host-rocks; b) pegmatite bodies with an adequate width; c) protracted heat supply or slow cooling rate simultaneously allowing strong constituent diffusion, steady nucleation and consistent growth rates

Serum lipids and prostate cancer

Background: Conflicting results are found in the literature relating serum lipids levels and prostate cancer. Some results imply a relationship between them; others contradict this association. The purpose of this study was to investigate a possible association between serum lipids levels and prostate cancer, at time of diagnosis. Methods: We measured serum levels of total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides in 237 patients submitted to a prostate biopsy, with PSA between 2 and 10 ng/ml. Patients without cancer at biopsy were used as controls, and the others were considered as cases. No information about lipid-lowering therapy, including statins, was available neither in cases nor in controls. Cases were divided into risk groups, according to the disease severity, based on staging. Lipids levels were compared between groups, using parametric and nonparametric tests. Logistic regression analysis and odds ratios were calculated. Results: LDL and total cholesterol levels were lower in patients with cancer, with the difference being statistically significant for LDL cholesterol (p = 0.010) and borderline for total cholesterol (p = 0.050). No significant differences were found between the several risk groups. Odds ratios for low LDL cholesterol (<130 mg/dl) and low total cholesterol (<200 mg/dl), with prostate cancer as the outcome, were 1.983 and 1.703, respectively. There were no significant differences between cases and controls for the other lipids. Conclusion: Lower LDL cholesterol (<130 mg/dl) and lower total cholesterol (<200 mg/dl) serum levels seem to associate with prostate cancer, at time of diagnosis.publishersversionpublishe

Dye assessment in nanostructured TiO2 sensitized films by microprobe techniques

Dye sensitized solar cells (DSCs) have received considerable attention once this technology offers economic and environmental advantages over conventional photovoltaic (PV) devices. The PV performance of a DSC relies on the characteristics of its photoanode, which typically consists of a nanocrystalline porous TiO2 film, enabled with a large adsorptive surface area. Dye molecules that capture photons from light during device operation are attached to the film nanoparticles. The effective loading of the dye in the TiO2 electrode is of utmost importance for controlling and optimizing solar cell parameters. Relatively few methods are known today for quantitative evaluation of the total dye adsorbed on the film. In this work, a new approach combining microprobe techniques namely, Ion Beam Analytical (IBA) techniques using a micro-ion beam (Rutherford Backscattering Spectrometry (RBS) and Particle Induced X-ray Emission (PIXE)) and Electron Probe Micro-Analysis (EPMA) was carried out to assess dye distribution and depth profile in TiO2 films and the dye load based on Ru/Ti mass ratio. Different 1D nanostructured TiO2 films were prepared, morphologically characterised by SEM, sensitized and analysed by the referred techniques. Dye load evaluation in different TiO2 films by three different techniques (PIXE, RBS and EPMA/ wavelength dispersive spectrometry (WDS)) provided similar results of Ru/Ti mass fraction ratio. Moreover, it was possible to assess dye surface distribution and its depth profile, by means of Ru signal, and to visualise the dye distribution in sample cross-section through X-ray mapping by EPMA/ energy dispersive spectrometry (EDS). PIXE maps of Ru and Ti indicated an homogeneous surface distribution. The assessment of ruthenium depth profile by RBS showed that some films have homogeneous Ru depth distribution while others present different Ru concentration in the top layer (2 ìm thickness). These results are consistent with the EPMA/EDS maps obtained. EPMA (WDS and EDS) together with IBA techniques proved to be powerful tools for functional materials characterisation and provided very promising results in the study of nanostructured TiO2 sensitized films

Assessment of dye distribution in sensitized solar cells by microprobe techniques

Dye sensitized solar cells (DSCs) have received considerable attention once this technology offers economic and environmental advantages over conventional photovoltaic (PV) devices. The PV performance of a DSC relies on the characteristics of its photoanode, which typically consists of a nanocrystalline porous TiO2 film, enabled with a large adsorptive surface area. Dye molecules that capture photons from light during device operation are attached to the film nanoparticles. The effective loading of the dye in the TiO2 electrode is of paramount relevance for controlling and optimizing solar cell parameters. Relatively few methods are known today for quantitative evaluation of the total dye adsorbed on the film. In this context, microprobe techniques come out as suitable tools to evaluate the dye surface distribution and depth profile in sensitized films. Electron Probe Microanalysis (EPMA) and Ion Beam Analytical (IBA) techniques using a micro-ion beam were used to quantify and to study the distribution of the Ru organometallic dye in TiO2 films, making use of the different penetration depth and beam sizes of each technique. Different 1D nanostructured TiO2 films were prepared, morphologically characterized by SEM, sensitized and analyzed by the referred techniques. Dye load evaluation in different TiO2 films by three different techniques (PIXE, RBS and EPMA/WDS) provided similar results of Ru/Ti mass fraction ratio. Moreover, it was possible to assess dye surface distribution and its depth profile, by means of Ru signal, and to visualize the dye distribution in sample cross-section through X-ray mapping by EPMA/EDS. PIXE maps of Ru and Ti indicated an homogeneous surface distribution. The assessment of Ru depth profile by RBS showed that some films have homogeneous Ru depth distribution while others present different Ru concentration in the top layer (2 lm thickness). These results are consistent with the EPMA/EDS maps obtained

Microscopy techniques for dye distribution in DSCs nanocrystalline TiO2 films

Capture of sunlight has attracted an increasing interest in the scientific community and triggered the development of efficient and cheap photovoltaic devices. Amongst recent generation technologies for solar energy conversion, dye-sensitized solar cells (DSCs) show an optimal trade-off between high-conversion efficiency and low-cost manufacturing. For the last two decades, significant progress has been made and best energy conversion efficiency of the DSC at the laboratory scale has surpassed 12% [1]. A lot of work has focused on the enlargement of surface areas to enhance the amount of adsorbed dyes by reduction of nanoparticle sizes or utilization of novel structures. Nevertheless there remain some crucial details of DSC operation for which limited information is available, namely dye diffusion and adsorption, surface coverage and dye distribution throughout the nc-TiO2 film. Microprobe techniques can be powerful tools to evaluate the dye load, the dye distribution and dye depth profile in sensitized films. Electron Probe Microanalysis (EPMA) and Ion Beam Analytical (IBA) techniques using a micro-ion beam, namely micro-Particle Induced X-ray Emission ( PIXE) and Rutherford Backscattering Spectrometry (RBS), were used to quantify and to study the distribution of the ruthenium organometallic (N719) dye in TiO2 films, profiting from the different penetration depth and beam sizes of each technique. Two different types of films were prepared and sensitized, mesoporous nanoparticles and 1D nanostructured TiO2 films (figure 1). Despite the low concentration of Ru, the high sensitive analytical techniques used allowed to assess the Ru surface distribution and depth profile. Fig. 2 shows the PIXE maps of Ru and Ti indicating an homogeneous surface distribution. The same figure presents the RBS spectra obtained with a 2 MeV proton beam of the same sample showing that a good spectra fit is obtained considering only two sample layers: the first one with a 1.7 ìm thickness; the second one being the SiO2 substrate. The Ru RBS signal also shows that the dye has an homogeneous depth distribution. Due to the fine spatial resolution of the EPMA/WDS (Wavelength Dispersive Spectroscopy) technique it was possible to visualise the dye distribution in sample cross-section (with micrometer or submicrometer dimensions) as presented in Fig. 3 for the elemental mapping of a mesoporous nanoparticle TiO2 film. Dye load evaluation by two different techniques (ìPIXE and EPMA/WDS) provided similar results (Ru/Ti values around 0.5 %). The distribution analysis of the organometallic dye (N719) was done through ruthenium distribution via X-ray mapping. RBS was used to assess the ruthenium depth profile. This assessment can lead to a better understanding of the device performance