SimTek - an edX-based platform for Mathematical Multi-physics Simulation

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BBIPED: BCAM-Baltogar Industrial Platform for Engineering Design

Currently, commercial software for computational fluid dynamics offers a good set of features to deal with traditional designs. Within a competitive market industrial innovation is a key factor that must be faced by companies. However, the design of solutions to deal with industrial challenges cannot be done within commercial software due to the lack of flexibility. Open source initiatives are a good option but the learning curve is high, specially for industrial engineers profiles. In this paper, we present the BBIPED platform which has been designed to deal with turbomachinery applications in a simple and friendly way. The main goal is to keep the platform as simpler as possible providing the enough flexibility to include out-of-the-box solutions to cope with industrial challenges. BBIPED platform provides links with currently existing remarkable open source initiatives altogether with our own developments. Particularly, it is remarkable a first approach for automatic mesh generation based on geometry parametrization solution, and the provision of novel techniques to deal with multiple rotating frame (MRF): Multizone MRF an Virtual MRF. Case tests were designed to test the solutions and to assess and validate the results against commercial suites with promising results

Lagged and instantaneous dynamical influences related to brain structural connectivity

Contemporary neuroimaging methods can shed light on the basis of human neural and cognitive specializations, with important implications for neuroscience and medicine. Different MRI acquisitions provide different brain networks at the macroscale; whilst diffusion-weighted MRI (dMRI) provides a structural connectivity (SC) coincident with the bundles of parallel fibers between brain areas, functional MRI (fMRI) accounts for the variations in the blood-oxygenation-level-dependent T2* signal, providing functional connectivity (FC).Understanding the precise relation between FC and SC, that is, between brain dynamics and structure, is still a challenge for neuroscience. To investigate this problem, we acquired data at rest and built the corresponding SC (with matrix elements corresponding to the fiber number between brain areas) to be compared with FC connectivity matrices obtained by 3 different methods: directed dependencies by an exploratory version of structural equation modeling (eSEM), linear correlations (C) and partial correlations (PC). We also considered the possibility of using lagged correlations in time series; so, we compared a lagged version of eSEM and Granger causality (GC). Our results were two-fold: firstly, eSEM performance in correlating with SC was comparable to those obtained from C and PC, but eSEM (not C nor PC) provides information about directionality of the functional interactions. Second, interactions on a time scale much smaller than the sampling time, captured by instantaneous connectivity methods, are much more related to SC than slow directed influences captured by the lagged analysis. Indeed the performance in correlating with SC was much worse for GC and for the lagged version of eSEM. We expect these results to supply further insights to the interplay between SC and functional patterns, an important issue in the study of brain physiology and function.Comment: Accepted and published in Frontiers in Psychology in its current form. 27 pages, 1 table, 5 figures, 2 suppl. figure

An Expert Systems for Homeopatic Glaucoma Treatment (SEHO)

In this article, an Expert System for Homeopathic Glaucoma Treatment (SEHO) is presented, the task of which is to assist ophthalmologists in selecting the most appropriate therapy for a patient diagnosed as having glaucoma. It is based on techniques proper to homeopathic medicine, a trend that is gaining more and more supporters all over the world, but in which real experts are few and far between. After a brief overview of the state of the art, the authors describe in detail on the development of the system, for which the IDEAL methodology, designed for knowledge-based system development, was used

Adaptação cultural e validação da versão portuguesa do questionário Medical Outcomes Study Social Support Survey (MOS-SSS)

O objectivo deste trabalho é calcular as propriedades psicométricas da versão portuguesa do questionário Medical Outcomes Study Social Support Survey (MOS-SSS). Este questionário foi traduzido e adaptado à cultura portuguesa. A amostra é constituída por 101 doentes com doença crónica, utentes de um centro de saúde rural de Portugal. A idade média é 63,4 anos; 56,4% são mulheres. 29% são analfabetos e 2% possuem estudos superiores. 78% sofrem de hipertensão arterial e 56,4% sofrem de diabetes mellitus tipo 2. A consistência interna foi avaliada com o alpha de Cronbach. Depois, foi realizada uma análise factorial exploratória e confirmatória com o objectivo de confirmar a validade e fiabilidade da escala e as suas características multidimensionais. A confiabilidade teste-reteste realizada às duas semanas foi estimada usando a análise kappa ponderado para as variáveis ordinais e o coeficiente de correlação intraclasse para as variáveis quantitativas. A alpha de Cronbach para as subescalas varia entre 0,873 e 0,967 no teste e 0,862 e 0,972 no reteste. A análise factorial exploratória revelou a existência de quatro factores (apoio emocional, material, afectivo e interacção social positiva) que explicam o 72,71% da variância. A análise factorial confirmatória permite concluir a existência destes quatro factores que permitem a aplicação da escala com os itens do questionário original. Os índices de ajustamento são satisfatórios e verificam a estrutura inicial, apresentando valores de χ2/df =2,01; GFI =0,998; CFI=0,999; AGFI =0,998; TLI =0,999; NFI =0,998; SRMR =0,332; RMSEA =0,76. A confiabilidade teste-reteste às duas semanas da versão portuguesa do MOS-SSS foi estimada pelo coeficiente de correlação intraclasse que variou entre 0,941 e 0,966 para as quatro dimensões do questionário e para o índice de apoio total. Os índices kappa ponderados variaram entre 0,67 e 0,87 para todos os itens. A versão portuguesa do MOS-SSS demonstrou boas características psicométricas e parece ser útil para avaliar as características multidimensionais do apoio social em população portuguesa.The aim of this study was the assesment of psychometric properties of the Portuguese version of the instrument «Medical Outcomes Study – Social Support Survey (MOSSSS) ». This questionnaire has been translated and adapted in a Portuguese sample of 101 patients with chronic illness of a rural health centre in Portugal. The average age of patients was 63.4 years, 56.4% female. 29% were illiterate and 2% had completed high school. 78% had arterial hypertension and the 56.4% had diabetes mellitus type 2. The internal consistency was evaluated using Cronbach’s alpha. Exploratory and Confirmatory factor analysis were performed in order to confirm reliability and validity of the scale and its multidimensional characteristics. The 2-week test-retest reliability was estimated using weighted kappa for the ordinals variables and intraclass coefficient correlation for the quantitative variables. Cronbach’s alphas for the subscales ranged from 0.873 to 0.967 at test, and 0.862 to 0.972 at retest. Exploratory factor analysis revealed the existence of four factors (emotional, tangible, positive interaction and affection support) that explain the 72.71% of the variance. Confirmatory factor analysis supported the existence of four factors that allowed the application of the scale with original items. The goodness-of-fit measures corroborate the initial structure, with χ2/ df=2.01, GFI=0.998, CFI=0.999, AGFI=0.998, TLI=0.999, NFI=0.998, SRMR=0.332, RMSEA=0.76. The 2-weeks test-retest reliability of the Portuguese MOS-SSS as measured by the intraclass correlation coefficient was ranged from 0.941 to 0.966 for the four dimensions and the overall support index. The weighted kappa was ranged from 0.67 to 0.87 for all the items. The MOS-SSS Portuguese version demonstrates good psychometric properties and seems to be useful to measure multidimensional aspects of social support in the Portuguese population.Sociedade Espanhola de Medicina Familiar e Comunitária (SEMFYC

CARMENES input catalogue of M dwarfs. I. Low-resolution spectroscopy with CAFOS

Context. CARMENES is a stabilised, high-resolution, double-channel spectrograph at the 3.5 m Calar Alto telescope. It is optimally designed for radial-velocity surveys of M dwarfs with potentially habitable Earth-mass planets. Aims. We prepare a list of the brightest, single M dwarfs in each spectral subtype observable from the northern hemisphere, from which we will select the best planet-hunting targets for CARMENES. Methods. In this first paper on the preparation of our input catalogue, we compiled a large amount of public data and collected low-resolution optical spectroscopy with CAFOS at the 2.2 m Calar Alto telescope for 753 stars. We derived accurate spectral types using a dense grid of standard stars, a double least-squares minimisation technique, and 31 spectral indices previously defined by other authors. Additionally, we quantified surface gravity, metallicity, and chromospheric activity for all the stars in our sample. Results. We calculated spectral types for all 753 stars, of which 305 are new and 448 are revised. We measured pseudo-equivalent widths of Halpha for all the stars in our sample, concluded that chromospheric activity does not affect spectral typing from our indices, and tabulated 49 stars that had been reported to be young stars in open clusters, moving groups, and stellar associations. Of the 753 stars, two are new subdwarf candidates, three are T Tauri stars, 25 are giants, 44 are K dwarfs, and 679 are M dwarfs. Many of the 261 investigated dwarfs in the range M4.0-8.0 V are among the brightest stars known in their spectral subtype. Conclusions. This collection of low-resolution spectroscopic data serves as a candidate target list for the CARMENES survey and can be highly valuable for other radial-velocity surveys of M dwarfs and for studies of cool dwarfs in the solar neighbourhood.Comment: A&A, in pres

Semantic Reference Model in Medical Time Series

The analysis of time series databases is very important in the area of medicine. Most of the approaches that address this problem are based on numerical algorithms that calculate distances, clusters, index trees, etc. However, a domain-dependent analyis sometimes needs to be conducted to search for the symblic rather than numerical characteristics of the time series. This paper focuses on our work on the discovery of reference models in time series of isokinetics data and a technique that transforms the numerical time series into symblic series. We briefly describe the algorithm used to create reference models for population groups an its application in the real world. Then, we describe a method based on extracting semantic information from a numerical series. This symbolic information helps users to effciently analyze and compare time series in the same or similar way as a domain expert would

On Chip Implementation of a Pixel-Parallel Approach for Retinal Vessel Tree Extraction

Abstract-Retinal vessel tree extraction from angiography images play an important role not only in the medical domain, but also in biometric identification applications. From the image processing point of view, a lot of algorithms and strategies have been developed to deal with this topic. Although reliable results have been obtained, the main disadvantage in most of these proposals is still the high computation effort required. In this paper, a methodology to extract the retinal vessel tree has been developed, specially defined in terms of fine grain SIMD processing with the purpose of improving the computation time. The proposal has been implemented on the SIMD processor array chip SCAMP-3. The execution times for the main modules of the proposed algorithm have been included to show its capability