306 research outputs found

    Hilos y nanotecnología: monitoreo de la señal pulso vital

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    This article shows the results obtained in the Threads and Nanotechnology research project, in which the monitoring of the vital pulse signal was developed. Through the application of concepts such as: the principles of photoplethysmography, piezoelectric sensors, Analog-Digital conversion and digital filters; allowing electronic handling, programming and testing of a microcontroller to send information to the element that processed the sensed signal. An Android and Web application was implemented for its correct visualization. The work finished with the construction of a device to facilitate early alarms of health status in older adults.Este artículo muestra los resultados obtenidos en el proyecto de investigación de Hilos y Nanotecnología, en el que se desarrolló el monitoreo de la señal pulso vital. Mediante la aplicación de conceptos tales como: los principios de fotopletismografía, sensores piezoeléctricos, conversión analógico-digital y filtros digitales, se establece el manejo electrónico, la programación y las pruebas de un microcontrolador para enviar información al elemento que procesó la señal detectada. Se implementó una aplicación Android y Web para su correcta visualización. El trabajo finaliza con la construcción de un dispositivo para facilitar las primeras alarmas del estado de salud en los adultos mayores

    A computational model for microbial colonisation of an antifouling surface

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    Biofouling of marine surfaces such as ship hulls is a major industrial problem. Antifouling (AF) paints delay the onset of biofouling by releasing biocidal chemicals. We present a computational model for microbial colonization of a biocide-releasing AF surface. Our model accounts for random arrival from the ocean of microorganisms with different biocide resistance levels, biocide-dependent proliferation or killing, and a transition to a biofilm state. Our computer simulations support a picture in which biocide-resistant microorganisms initially form a loosely attached layer that eventually transitions to a growing biofilm. Once the growing biofilm is established, immigrating microorganisms are shielded from the biocide, allowing more biocide-susceptible strains to proliferate. In our model, colonization of the AF surface is highly stochastic. The waiting time before the biofilm establishes is exponentially distributed, suggesting a Poisson process. The waiting time depends exponentially on both the concentration of biocide at the surface and the rate of arrival of resistant microorganisms from the ocean. Taken together our results suggest that biofouling of AF surfaces may be intrinsically stochastic and hence unpredictable, but immigration of more biocide-resistant species, as well as the biological transition to biofilm physiology, may be important factors controlling the time to biofilm establishment

    Design patterns for the development of electronic health record-driven phenotype extraction algorithms

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    AbstractBackgroundDesign patterns, in the context of software development and ontologies, provide generalized approaches and guidance to solving commonly occurring problems, or addressing common situations typically informed by intuition, heuristics and experience. While the biomedical literature contains broad coverage of specific phenotype algorithm implementations, no work to date has attempted to generalize common approaches into design patterns, which may then be distributed to the informatics community to efficiently develop more accurate phenotype algorithms.MethodsUsing phenotyping algorithms stored in the Phenotype KnowledgeBase (PheKB), we conducted an independent iterative review to identify recurrent elements within the algorithm definitions. We extracted and generalized recurrent elements in these algorithms into candidate patterns. The authors then assessed the candidate patterns for validity by group consensus, and annotated them with attributes.ResultsA total of 24 electronic Medical Records and Genomics (eMERGE) phenotypes available in PheKB as of 1/25/2013 were downloaded and reviewed. From these, a total of 21 phenotyping patterns were identified, which are available as an online data supplement.ConclusionsRepeatable patterns within phenotyping algorithms exist, and when codified and cataloged may help to educate both experienced and novice algorithm developers. The dissemination and application of these patterns has the potential to decrease the time to develop algorithms, while improving portability and accuracy

    Desiderata for the development of next-generation electronic health record phenotype libraries

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    BackgroundHigh-quality phenotype definitions are desirable to enable the extraction of patient cohorts from large electronic health record repositories and are characterized by properties such as portability, reproducibility, and validity. Phenotype libraries, where definitions are stored, have the potential to contribute significantly to the quality of the definitions they host. In this work, we present a set of desiderata for the design of a next-generation phenotype library that is able to ensure the quality of hosted definitions by combining the functionality currently offered by disparate tooling.MethodsA group of researchers examined work to date on phenotype models, implementation, and validation, as well as contemporary phenotype libraries developed as a part of their own phenomics communities. Existing phenotype frameworks were also examined. This work was translated and refined by all the authors into a set of best practices.ResultsWe present 14 library desiderata that promote high-quality phenotype definitions, in the areas of modelling, logging, validation, and sharing and warehousing.ConclusionsThere are a number of choices to be made when constructing phenotype libraries. Our considerations distil the best practices in the field and include pointers towards their further development to support portable, reproducible, and clinically valid phenotype design. The provision of high-quality phenotype definitions enables electronic health record data to be more effectively used in medical domains

    The Canadian Women's Heart Health Alliance atlas on the epidemiology, diagnosis, and management of cardiovascular disease in women - Chapter 6 : sex- and gender-specific diagnosis and treatment

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    This chapter summarizes the sex- and gender-specific diagnosis and treatment of acute/unstable presentations and nacute/stable presentations of cardiovascular disease in women. Guidelines, scientific statements, systematic reviews/meta-analyses, and primary research studies related to diagnosis and treatment of coronary artery disease, cerebrovascular disease (stroke), valvular heart disease, and heart failure in women were reviewed. The evidence is summarized as a narrative, and when available, sex- and gender-specific practice and research recommendations are provided. Acute coronary syndrome presentations and emergency department delays are different in women than they are in men. Coronary angiography remains the gold-standard test for diagnosis of obstructive coronary artery disease. Other diagnostic imaging modalities for ischemic heart disease detection (eg, positron emission tomography, echocardiography, single-photon emission computed tomography, cardiovascular magnetic resonance, coronary computed tomography angiography) have been shown to be useful in women, with their selection dependent upon both the goal of the individualized assessment and the testing resources available. Noncontrast computed tomography and computed tomography angiography are used to diagnose stroke in women. Although sex-specific differences appear to exist in the efficacy of standard treatments for diverse presentations of acute coronary syndrome, many cardiovascular drugs and interventions tested in clinical trials were not powered to detect sex-specific differences, and knowledge gaps remain. Similarly, although knowledge is evolving about sex-specific difference in the management of valvular heart disease, and heart failure with both reduced and preserved ejection fraction, current guidelines are lacking in sex-specific recommendations, and more research is needed.Ce chapitre prĂ©sente un rĂ©sumĂ© sur le diagnostic et le traitement des tableaux cliniques aigus/instables et non aigus/stables des maladies cardiovasculaires chez les femmes, et les diffĂ©rences propres Ă  chacun des deux sexes. Les lignes directrices, les Ă©noncĂ©s scientifiques, les revues systĂ©matiques/mĂ©ta-analyses et les Ă©tudes de recherche originale sur le diagnostic et le traitement des coronaropathies, des maladies vasculaires cĂ©rĂ©brales (AVC), des valvulopathies cardiaques et de l’insuffisance cardiaque chez les femmes ont Ă©tĂ© examinĂ©s. Les donnĂ©es probantes sont rĂ©sumĂ©es sous forme narrative et, lorsqu’elles sont disponibles, des recommandations en matiĂšre de pratique et de recherche pour chacun des deux sexes sont prĂ©sentĂ©es. Les tableaux cliniques du syndrome coronarien aigu et les dĂ©lais d’attente Ă  l’urgence sont diffĂ©rents selon qu’une femme ou un homme en est atteint. L’angiographie coronarienne reste l’examen de rĂ©fĂ©rence pour le diagnostic des coronaropathies obstructives. D’autres examens d’imagerie diagnostique (p. ex. la tomographie par Ă©mission de positons, l’échocardiographie, la tomographie d'Ă©mission Ă  photon unique, la rĂ©sonance magnĂ©tique cardiovasculaire, l’angiographie coronarienne par tomodensitomĂ©trie) se sont avĂ©rĂ©s utiles pour la dĂ©tection des cardiopathies ischĂ©miques chez les femmes. Le recours Ă  ces modalitĂ©s dĂ©pend de l’objectif de l’évaluation personnalisĂ©e et des ressources disponibles. La tomodensitomĂ©trie sans agent de contraste et l’angiographie par tomodensitomĂ©trie sont utilisĂ©es pour le diagnostic des AVC chez les femmes. MalgrĂ© les diffĂ©rences entre les sexes quant Ă  l’efficacitĂ© des traitements de rĂ©fĂ©rence des divers tableaux cliniques du syndrome coronarien aigu, bon nombre des mĂ©dicaments et des interventions cardiovasculaires qui ont fait l’objet d’essais cliniques n’avaient pas la puissance statistique nĂ©cessaire pour dĂ©tecter des diffĂ©rences selon les sexes, de sorte que les connaissances restent fragmentaires sur ce sujet. De mĂȘme, malgrĂ© l’évolution des connaissances sur les diffĂ©rences sexuelles quant Ă  la prise en charge des valvulopathies cardiaques et de l’insuffisance cardiaque avec fraction d’éjection rĂ©duite ou prĂ©servĂ©e, on ne trouve pas de recommandations pour chaque sexe dans les lignes directrices actuelles, d’oĂč la pertinence d’études supplĂ©mentaires portant sur cette question

    Specific immune modulation of experimental colitis drives enteric alpha-synuclein accumulation and triggers age-related Parkinson-like brain pathology

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    Background: In some people with Parkinson’s disease (PD), a-synuclein (αSyn) accumulation may begin in the enteric nervous system (ENS) decades before development of brain pathology and disease diagnosis. Objective: To determine how different types and severity of intestinal inflammation could trigger αSyn accumulation in the ENS and the subsequent development of αSyn brain pathology. Methods: We assessed the effects of modulating short- and long-term experimental colitis on αSyn accumulation in the gut of αSyn transgenic and wild type mice by immunostaining and gene expression analysis. To determine the long-term effect on the brain, we induced dextran sulfate sodium (DSS) colitis in young αSyn transgenic mice and aged them under normal conditions up to 9 or 21 months before tissue analyses. Results: A single strong or sustained mild DSS colitis triggered αSyn accumulation in the submucosal plexus of wild type and αSyn transgenic mice, while short-term mild DSS colitis or inflammation induced by lipopolysaccharide did not have such an effect. Genetic and pharmacological modulation of macrophage-associated pathways modulated the severity of enteric αSyn. Remarkably, experimental colitis at three months of age exacerbated the accumulation of aggregated phospho-Serine 129 αSyn in the midbrain (including the substantia nigra), in 21- but not 9-month-old αSyn transgenic mice. This increase in midbrain αSyn accumulation is accompanied by the loss of tyrosine hydroxylase-immunoreactive nigral neurons. Conclusions: Our data suggest that specific types and severity of intestinal inflammation, mediated by monocyte/macrophage signaling, could play a critical role in the initiation and progression of PD

    Contemporaneous Observations of Direct and Raman Scattered O VI in Symbiotic Stars

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    Symbiotic stars are binary systems consisting of a hot star, typically a white dwarf, and a cool giant companion. The wind from the cool star is ionized by the radiation from the hot star, resulting in the characteristic combination of sharp nebular emission lines and stellar molecular absorption lines in the optical spectrum. Most of the emission lines are readily identifiable with common ions. However, two strong, broad emission lines at λλ\lambda\lambda 6825, 7082 defied identification with known atoms and ions. In 1989 Schmid made the case that these long unidentified emission lines resulted from the Raman scattering of the O VI resonance photons at λλ\lambda\lambda 1032, 1038 by neutral hydrogen. We present contemporaneous far-UV and optical observations of direct and Raman scattered O VI lines for nine symbiotic stars obtained with the Hopkins Ultraviolet Telescope (Astro-2) and various ground-based telescopes. The O VI emission lines are present in every instance in which the λλ\lambda\lambda 6825, 7082 lines are present in support of the Schmid Raman scattering model. We calculate scattering efficiencies and interpret the results in terms of the Raman models. Additionally, we measure the flux of the Fe II fluorescence line at λ\lambda1776, which is excited by the O VI line at λ\lambda1032, and calculate the first estimates of the conversion efficiencies of this process.Comment: 48 pages, 5 figure
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