Statistical modelling of railway track geometry degradation using hierarchical Bayesian models

Railway maintenance planners require a predictive model that can assess the railway track geometry degradation. The present paper uses a hierarchical Bayesian model as a tool to model the main two quality indicators related to railway track geometry degradation: the standard deviation of longitudinal level defects and the standard deviation of horizontal alignment defects. Hierarchical Bayesian Models (HBM) are flexible statistical models that allow specifying different spatially correlated components between consecutive track sections, namely for the deterioration rates and the initial qualities parameters. HBM are developed for both quality indicators, conducting an extensive comparison between candidate models and a sensitivity analysis on prior distributions. HBM is applied to provide an overall assessment of the degradation of railway track geometry, for the main Portuguese railway line Lisbon-Oporto

Assessing the potential cost savings of introducing the maintenance option of ‘Economic Tyre Turning’ in Great Britain railway wheelsets

This paper assesses the potential cost savings of introducing a maintenance option known as ‘Economic Tyre Turning’ (ETT) in railway wheelset maintenance in Great Britain. It first develops a life-cycle cost model and puts forward a Monte Carlo simulation procedure to assess the life-cycle costs of different maintenance strategies, including ETT. This Monte Carlo simulation procedure samples from statistical degradation models that estimate the evolution of wear and damage trajectories of different wheelsets, and the maintenance impact of wheel turning in the loss of diameter in a more realistic manner by controlling random effects related to unit, vehicle and month of measurement. The main findings suggest that ETT may provide potential savings of around 0.8% up to 4.4% when compared to a simple wheelset renewal strategy, and between 2.0% and 4.7% cost savings when ETT is used in association with more complex strategies

As TIC na educação de alunos cegos e com baixa visão. a perspetiva dos professores das escolas de referência

Considering the changes that technological evolution has provoked in the education system and the fact that Information and Communication Technologies (ICT) cannot be dissociated from the pedagogical practices adopted with blind or visual impaired students, for the study and understanding of this reality, it is essential to assess the opinion of the professionals who work daily in the educational process of these students with special needs. This research, predominantly quantitative, intends to analyze the teacher’s perceptions, who teach blind or visually impaired students of 2nd and 3rd cycles of primary and secondary education in the reference schools for the education of blind or visual impaired students, in mainland Portugal, of their knowledge, teaching and training in this area of ICT. The results reveal a sample confident in their technological capabilities, however with little resourcefulness in some tools and applications specific to the area of visual impairment and blindness, and a very significant number of teachers ignoring many of these. Another finding is that the lack of specific training is considered the main obstacle for teachers, with regard to a real integration of ICT in the teaching and learning of these students.Considerando as mudanças que a evolução tecnológica tem provocado no sistema educativo e não podendo as Tecnologias de Informação e Comunicação (TIC) ser desvinculadas das práticas pedagógicas adotadas com os alunos cegos e com baixa visão, para o estudo e compreensão desta realidade, é fundamental aferir a opinião dos profissionais que trabalham diariamente em prol do processo educativo destes alunos com necessidades educativas especiais. Este estudo, de natureza predominantemente quantitativa, pretende analisar a perceção dos docentes que lecionam alunos com deficiência visual, do 2.º e 3.º ciclos do ensino básico e do ensino secundário, nas escolas de referência para a educação de alunos cegos e com baixa visão, em Portugal Continental, sobre os seus conhecimentos, práticas pedagógicas e formação na área das TIC, visando o ensino e aprendizagem dos mesmos. Os resultados revelam uma amostra confiante nas suas capacidades tecnológicas, contudo com manifestas lacunas no que diz respeito ao conhecimento e desenvoltura em algumas ferramentas e aplicações informáticas específicas para a área da deficiência visual. Uma outra constatação é o facto de a falta de formação específica ser o principal obstáculo considerado pelos docentes no que respeita a uma real integração das TIC no processo educativo destes alunos

Aprendizagem em Contexto Simulado: Normas de Procedimento de Enfermagem: Volume IV

info:eu-repo/semantics/publishedVersio

Automatic verification of design rules in PCB manufacturing

Nowadays, electronics can be found in almost every available device. At the core of electronic devices there are Printed Circuit Boards (PCB). To create a suitable PCB there is the need of complying with several constraints, both concerning electrical and layout design. Thus, the design rules related to the PCB manufacturing and assembly are very important since these restrictions are fundamental to ensure the creation of a viable physical PCB. Electrical Computer Aided Design (ECAD) tools are able to automatically verify such rules, but they only consider a subset of the total required rules. The remaining rules are currently manually checked, which may increase the occurrence of errors and, consequently, increase the overall costs in designing and in the manufacturing process of a PCB. Being the design a crucial phase in the manufacturing procedure, a software system that automatically verifies all design rules and produce the corresponding assessment report is fundamental. Such software system is addressed in this paper.This work was funded by the project “iFACTORY: Novas Capacidades de Industrialização”, with reference 002814 supported by FEDER trough “Portugal2020 Programa Operacional Competitividade e Internacionalização” (COMPETE2020). This work has been supported by COMPETE: POCI-01-0145-FEDER-007043and FCT - Fundação para a Ciência e a Tecnologia within the Project Scope: UID/CEC/00319/201

insights from an echo and cardiovascular magnetic resonance study of patients referred for surgical aortic valve replacement

AIMS: This study aims to assess the prevalence of relative apical sparing pattern (RASP) in patients with severe symptomatic aortic stenosis (AS), referred for surgical aortic valve replacement (AVR), to evaluate its significance, possible relation to amyloid deposition, and persistence after surgery. METHODS AND RESULTS: Prospective study of 150 consecutive patients [age 73 (interquartile range: 68-77), 51% women], with severe symptomatic AS referred to surgical AVR. All patients underwent cardiac magnetic resonance (CMR) before surgery. RASP was defined by [average apical longitudinal strain (LS)/(average basal LS + average mid LS)] > 1 by echocardiography. AVR was performed in 119 (79.3%) patients. Both Congo red and sodium sulphate-Alcian blue (SAB) stain were used to exclude amyloid on septal myocardial biopsy. LV remodelling and tissue characterization parameters were compared in patients with and without RASP. Deformation pattern was re-assessed at 3-6 months after AVR.RASP was present in 23 patients (15.3%). There was no suspicion of amyloid at pre-operative CMR [native T1 value 1053 ms (1025-1076 ms); extracellular volume (ECV) 28% (25-30%)]. None of the patients had amyloid deposition at histopathology. Patients with RASP had significantly higher pre-operative LV mass and increased septal wall thickness. They also had higher N-terminal pro b-type natriuretic peptide (NT-proBNP) levels [1564 (766-3318) vs. 548 (221-1440) pg/mL, P = 0.010], lower LV ejection fraction (53.7 ± 10.5 vs. 60.5 ± 10.2%, P = 0.005), and higher absolute late gadolinium enhancement (LGE) mass [9.7 (5.4-14.1) vs. 4.8 (1.9-8.6) g, P = 0.016] at CMR. Follow-up evaluation after AVR revealed RASP disappearance in all except two of the patients. CONCLUSION: RASP is not specific of cardiac amyloidosis. It may also be found in severe symptomatic AS without amyloidosis, reflecting advanced LV disease, being mostly reversible after surgery.publishersversionepub_ahead_of_prin

SARS-CoV-2 introductions and early dynamics of the epidemic in Portugal

Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration with more than 50 laboratories distributed nationwide. Methods By applying recent phylodynamic models that allow integration of individual-based travel history, we reconstructed and characterized the spatio-temporal dynamics of SARSCoV-2 introductions and early dissemination in Portugal. Results We detected at least 277 independent SARS-CoV-2 introductions, mostly from European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland), which were consistent with the countries with the highest connectivity with Portugal. Although most introductions were estimated to have occurred during early March 2020, it is likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the first cases were confirmed. Conclusions Here we conclude that the earlier implementation of measures could have minimized the number of introductions and subsequent virus expansion in Portugal. This study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.We gratefully acknowledge to Sara Hill and Nuno Faria (University of Oxford) and Joshua Quick and Nick Loman (University of Birmingham) for kindly providing us with the initial sets of Artic Network primers for NGS; Rafael Mamede (MRamirez team, IMM, Lisbon) for developing and sharing a bioinformatics script for sequence curation (https://github.com/rfm-targa/BioinfUtils); Philippe Lemey (KU Leuven) for providing guidance on the implementation of the phylodynamic models; Joshua L. Cherry (National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health) for providing guidance with the subsampling strategies; and all authors, originating and submitting laboratories who have contributed genome data on GISAID (https://www.gisaid.org/) on which part of this research is based. The opinions expressed in this article are those of the authors and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government. This study is co-funded by Fundação para a Ciência e Tecnologia and Agência de Investigação Clínica e Inovação Biomédica (234_596874175) on behalf of the Research 4 COVID-19 call. Some infrastructural resources used in this study come from the GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by Fundação para a Ciência e a Tecnologia (FCT).info:eu-repo/semantics/publishedVersio

New data on the chronology of the Vale do Forno sedimentary sequence (Lower Tejo River terrace staircase) and its relevance as a fluvial archive of the Middle Pleistocene in western Iberia

The Vale do Forno archaeological sites (Alpiar\ue7a, central Portugal) document the earliest human occupation in the Lower Tejo River, well established in geomorphological and environmental terms, within the Middle Pleistocene. In a staircase of six fluvial terraces, the Palaeolithic sites were found on the T4 terrace (\ufe24 m, above river bed) which is made of a basal Lower Gravels unit (LG) and an overlying Upper Sands unit (US). Geomorphological mapping, coupled with lithostratigraphy, sedimentology and luminescence dating (quartz-OSL and K-feldspar post-IRIR290) were used in this study. The oldest artefacts found in the LG unit show crude bifacial forms that can be attributed to the Acheulian. In contrast, the US unit has archaeological sites stratigraphically documenting successive phases of an evolved Acheulian. Luminescence dating and correlation with the Marine Isotopic Stages suggest that the LG unit has a probable age of ca. 335 to 325 ka and the US unit an age of ca. 325 to 155 ka. This is in contrast to previous interpretations ascribing this terrace (and lithic industries) to the Last Interglacial and early phases of the Last Glacial. The VF3 site (Milharos), containing Micoquian (Final Acheulian) industries (with fine and elaborated bifaces), found in a stratigraphic level located between the T4 terrace deposits and a colluvium associated with Late Pleistocene aeolian sands, is younger than 155 ka but much older than 32 ka

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

A História da Alimentação: balizas historiográficas

Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema