A Graph Approach to Observability in Physical Sparse Linear Systems

A sparse linear system constitutes a valid model for a broad range of physical systems, such as electric power networks, industrial processes, control systems or traffic models. The physical magnitudes in those systems may be directly measured by means of sensor networks that, in conjunction with data obtained from contextual and boundary constraints, allow the estimation of the state of the systems. The term observability refers to the capability of estimating the state variables of a system based on the available information. In the case of linear systems, diffierent graphical approaches were developed to address this issue. In this paper a new unified graph based technique is proposed in order to determine the observability of a sparse linear physical system or, at least, a system that can be linearized after a first order derivative, using a given sensor set. A network associated to a linear equation system is introduced, which allows addressing and solving three related problems: the characterization of those cases for which algebraic and topological observability analysis return contradictory results; the characterization of a necessary and sufficient condition for topological observability; the determination of the maximum observable subsystem in case of unobservability. Two examples illustrate the developed techniques

Less is more : a comprehensive study on the effects of the unmber of gas diffusion layers on air-cathode microbial fuel cells

Altres ajuts: Acord transformatiu CRUE-CSICAir-cathode microbial fuel cells (AC-MFC) use a gas-diffusion-layer (GDL) coating based on polytetrafluoroethylene applied to the cathode to prevent electrolyte leakage. However, this type of GDL can also lead to a decrease in MFC performance due to electron-transfer limitation, mass-transfer limitation or catalyst availability. This study provides a comprehensive understanding of the significance of the GDL coating, demonstrating the interaction between the number of GDL coatings and the external resistance (Rext) used. An experimental design in 28 mL AC-MFCs was prepared and conducted using two different Rext (10 and 249 Ω) and four different GDL coatings (1 to 4 layers). The coating effect was not significant when operating with a high Rext, where the electron transfer was the limiting process. However, when the Rext was low, the amount of polytetrafluoroethylene limited the cathode performance due to a significant decrease in the Pt availability on the catalytic surface. Thus, GDL-1 with 10 Ω as Rext reached 0.96 mA/cm2, 3-fold higher than that obtained with 249 Ω as Rext (ca. 0.30 mA/cm2). Besides, the current density did not vary noticeably in the other cathodes with 249 Ω as Rext. Contrarily, the current density with 10 Ω as Rext decreased as the number of GDL increased (0.74, 0.57 and 0.37 for GDL-2, GDL-3 and GDL-4 respectively). These values agreed with those of the polarization curve. Furthermore, limitations were also observed in electrochemical impedance spectroscopy measurements: the charge resistance increased with the number of GDL, related to the ease of electron flow. These values were18 Ω, 22 Ω, 53 Ω and 58 Ω for GDL-1, GDL-2, GDL-3 and GDL-4, respectively, for both 10 and 249 Ω cathodes

Identificación de zonas de inundación a partir de imágenes (SAR) y de eventos históricos de inundación: caso de estudio Santiago de Cali, Colombia

The objective of this work was to identify flood zones in the city of Santiago de Cali Colombia, through historical information and RADAR images. During the process Sentinel 1 images pre and post event were used, and reports of hydrometeorological phenomena (1986-2018) were revisited. The method used corresponds to the framework named methodological complementarity and was carried out with the documentary review, fieldwork and the digital treatment of data based on supervised classification. The results of documentary review and fieldwork indicate the occurrence of 766 events associated with floods that have affected 186 neighborhoods in a period of 32 years. In addition to this, digital image processing identified 2082, 25 hectares of floodplains, with overall reliability of 89 percent. Kappa index of 0.76 percent. It is important to note that the majority of water plates were located in areas adjacent to the Cauca, Cali and Interceptor Sur and Oriental channels.El objetivo de este trabajo fue identificar zonas de inundación en la ciudad de Santiago de Cali Colombia, mediante imágenes de RADAR e información histórica. Durante el proceso se utilizaron imágenes Sentinel 1 pre y post evento y reportes de fenómenos hidrometereológicos (1986-2018). El método empleado precisó un abordaje desde diferentes ángulos, en lo que se enmarca como complementariedad metodológica. Consistió en una revisión documental, reconocimiento de campo, y el tratamiento digital de datos a partir de clasificación supervisada. Los resultados de la revisión documental y el trabajo de campo indican la ocurrencia de 766 eventos asociados a inundación que han afectado a 186 barrios en un periodo de 32 años. Además de esto, el procesamiento digital de las imágenes identificó 2082, 25 hectáreas inundables, con fiabilidad global del 89 por ciento e índice Kappa de 0.76 por ciento. Es importante resaltar que la mayoría de áreas inundables se localizaron en zonas adyacentes a los ríos Cauca, Cali y a los canales Interceptor Sur y Oriental

Protumorigenic effects of Snail-expression fibroblasts on colon cancer cells

et al.Snail1 is a transcriptional factor that plays an important role in epithelial–mesenchymal transition and in the acquisition of invasive properties by epithelial cells. In colon tumors, Snail1 expression in the stroma correlates with lower specific survival of cancer patients. However, the role(s) of Snail1 expression in stroma and its association with patients' survival have not been determined. We used human primary carcinoma-associated fibroblasts (CAFs) or normal fibroblasts (NFs) and fibroblast cell lines to analyze the effects of Snail1 expression on the protumorigenic capabilities in colon cancer cells. Snail1 expression was higher in CAFs than in NFs and, as well as α-SMA, a classic marker of activated CAFs. Moreover, in tumor samples from 50 colon cancer patients, SNAI1 expression was associated with expression of other CAF markers, such as α-SMA and fibroblast activation protein. Interestingly, coculture of CAFs with colon cells induced a significant increase in epithelial cell migration and proliferation, which was associated with endogenous SNAI1 expression levels. Ectopic manipulation of Snail1 in fibroblasts demonstrated that Snail1 expression controlled migration as well as proliferation of cocultured colon cancer cells in a paracrine manner. Furthermore, expression of Snail1 in fibroblasts was required for the coadjuvant effect of these cells on colon cancer cell growth and invasion when coxenografted in nude mice. Finally, cytokine profile changes, particularly MCP-3 expression, in fibroblasts are put forward as mediators of Snail1-derived effects on colon tumor cell migration. In summary, these studies demonstrate that Snail1 is necessary for the protumorigenic effects of fibroblasts on colon cancer cells.This research was supported by the PI12/02037, Fundación Científica AECC, SAF2010-20750, S2010/BMD-2344, RTICC-RD12/0036/0041 and by the Fundación Banco Santander. Antonio García de Herreros’ laboratory was supported by RTICC-RD12/0036/0005 and SAF 2010-16089. Ma Jesús Larriba’s laboratory was supported by RD12/0036/0021. Cristina Peña and José Miguel García are recipients of Miguel Servet Contracts from the Instituto de Salud Carlos III.Peer reviewe

Influence of Mesenchymal Stem Cell Sources on Their Regenerative Capacities on Different Surfaces

Current gold-standard strategies for bone regeneration do not achieve the optimal recovery of bone biomechanical properties. To bypass these limitations, tissue engineering techniques based on hybrid materials made up of osteoprogenitor cells—such as mesenchymal stem cells (MSCs)—and bioactive ceramic scaffolds—such as calcium phosphate-based (CaPs) bioceramics—seem promising. The biological properties of MSCs are influenced by the tissue source. This study aims to define the optimal MSC source and construct (i.e., the MSC–CaP combination) for clinical application in bone regeneration. A previous iTRAQ analysis generated the hypothesis that anatomical proximity to bone has a direct effect on MSC phenotype. MSCs were isolated from adipose tissue, bone marrow, and dental pulp, then cultured both on a plastic surface and on CaPs (hydroxyapatite and β-tricalcium phosphate), to compare their biological features. On plastic, MSCs isolated from dental pulp (DPSCs) presented the highest proliferation capacity and the greatest osteogenic potential. On both CaPs, DPSCs demonstrated the greatest capacity to colonise the bioceramics. Furthermore, the results demonstrated a trend that DPSCs had the most robust increase in ALP activity. Regarding CaPs, β-tricalcium phosphate obtained the best viability results, while hydroxyapatite had the highest ALP activity values. Therefore, we propose DPSCs as suitable MSCs for cell-based bone regeneration strategies

Alteraciones morfológicas de las médulas óseas en pacientes con covid-19. revision sistemática y meta-análisis

Introduction: Despite the fact that hematological alterations at the peripheral level are widely known, little is known about the alterations caused by COVID-19 at the bone marrow level. Objective: To determine the morphological alterations of the bone marrow caused by COVID-19. Material and methods: Systematic review and meta-analysis. Observational studies and reports and case series were included and editorials, reviews, letters to the editor were excluded. A search was performed in Pubmed, ScienceDirect and Scielo. The risk of bias was assessed using the NewCatell-Ottawa and Hassan Murad scales for case reports and series. The outcomes were the morphological parameters of the bone marrow. For the quantitative synthesis of the information, a proportion meta-analysis was performed using random effects in RStudio. Results: Hypercellularity occurred in 65% (95% CI: 51%-78%), maturation arrest of the myeloid series occurred in 57% (95% CI: 29%-83%). and the alteration of the M/E ratio occurred in 60% (95% CI: 46%-74%). Conclusion: The most frequent morphological alterations in the bone marrow were hypercellularity, arrest in myeloid maturation and alteration of the M/E ratio in patients with COVID-19.Introducción: Pese a conocerse ampliamente las alteraciones hematológicas a nivel periférico, aún es poco lo que se conoce acerca de las alteraciones originadas por la COVID-19 a nivel de la médula ósea. Objetivo: Determinar las alteraciones morfológicas de la médula ósea causadas por la COVID-19. Material y Métodos: Revisión sistemática y meta-análisis. Se incluyeron estudios observacionales y reportes y series de caso y se excluyeron a editoriales, revisiones y cartas al editor. Se realizó una búsqueda estructurada en Pubmed, ScienceDirect y Scielo. El riesgo de sesgo se evaluó mediante la escala NewCatell-Otawa y de Hassan Murad para los reportes y series de caso. Los desenlaces fueron los parámetros morfológicos de la médula ósea. Para la síntesis cuantitativa de la información se realizó un meta-análisis de proporción mediante efectos aleatorios en RStudio. Resultados: La hipercelularidad se presentó en el 65% (IC-95%: 51%-78%), la detención de la maduración de la serie mieloide se presentó en el 57% (IC-95%: 29%-83%) y la alteración de la relación M/E se presentó en el 60% (IC-95%: 46%-74%). Conclusión: Las alteraciones morfológicas en la médula ósea más frecuentes fueron la hipercelularidad, detención en la maduración mieloide y alteración de la relación M/E en los pacientes con COVID-19

Adaptación de las asignaturas básicas de primer curso de la ETSI Navales de la UPM: Actividades 2008-2009

En el marco de la reforma de las titulaciones con motivo del Espacio Europeo de Educación un grupo de profesores hemos coordinado, durante el curso 2008-2009, todas las asignaturas básicas de primer curso y una más de segundo curso en la Escuela Técnica Superior de Ingenieros Navales. Las actividades realizadas son: a) Coordinación de todas las asignaturas básicas de primer curso, con reuniones periódicas de coordinación horizontal y el establecimiento de una página web de moodle para profesores como espacio para el trabajo cooperativo. Particularmente importante es el establecimiento de un calendario conjunto de pruebas de evaluación continua. b) Redacción de guías de aprendizaje, con un formato común para todas las asignaturas, incluyendo los objetivos formativos, los contenidos, las actividades formativas, los enlaces y la bibliografía. c) Establecimiento de una plataforma de teleeducación común para todas las asignaturas, uno de los objetivos fundamentales del proyecto, ya que coexistían dos plataformas distintas. Igualmente importante ha sido reforzar los contenidos y las actividades que se podían realizar en la plataforma. d) Seguimiento del tiempo dedicado por los alumnos, hemos ido siguiendo el tiempo dedicado por los alumnos a las distintas asignaturas, para detectar si el tiempo que se dedica está en los márgenes establecidos en los créditos ECTS. Igualmente, hemos hecho dos encuestas a la mitad de cada semestre, para recoger las opiniones de los alumnos sobre las asignaturas y sobre los aspectos relevantes del proyecto. e) Organización de actividades de nivelación, para los alumnos de nuevo ingreso, con la organización de cursos cero y la participación y coordinación en la Plataforma de Punto de inicio de la UPM. f) Organización de actividades formativas, para poder llevar a cabo estas tareas, hemos organizado, en colaboración con el Centro y el Gabinete de Tele-Educación (GATE) actividades formativas relacionadas con la plataforma moodle, métodos de evaluación y de formación en competencias.En la presentación haremos una descripción de las actividades realizadas, así como una primera evaluación de las mismas. Por último, describiremos las tareas a desarrollar en los próximos cursos

Adaptación de las asignaturas básicas de primer curso de la ETSI Navales de la UPM: Primeras experiencias

En el marco de la reforma de las titulaciones con motivo de la puesta en marcha del Espacio Europeo de Educación Superior, un grupo de profesores hemos decidido coordinar todas las asignaturas básicas de primer curso y una asignatura de segundo curso en la Escuela Técnica Superior de Ingenieros Navales de la Universidad Politécnica de Madrid con el fin de dar una visión mas homogénea y compacta al alumno de lo que debe ser la formación básica del ingeniero. Para llevar a cabo dicho fin, la Universidad nos ha concedido un Proyecto de Innovación Educativa en la convocatoria 2008 para poder alcanzar una serie de objetivos en el curso 2008-2009, como son la coordinación de todas las asignaturas básicas de primer curso, la aplicación de nuevas metodologías en la práctica educativa, y una mejor adaptación de los alumnos de nuevo ingreso

Impact of SARS-Cov-2 infection in patients with hypertrophic cardiomyopathy : results of an international multicentre registry

To describe the natural history of SARS-CoV-2 infection in patients with hypertrophic cardiomyopathy (HCM) compared with a control group and to identify predictors of adverse events. Three hundred and five patients [age 56.6 ± 16.9 years old, 191 (62.6%) male patients] with HCM and SARS-Cov-2 infection were enrolled. The control group consisted of 91 131 infected individuals. Endpoints were (i) SARS-CoV-2 related mortality and (ii) severe clinical course [death or intensive care unit (ICU) admission]. New onset of atrial fibrillation, ventricular arrhythmias, shock, stroke, and cardiac arrest were also recorded. Sixty-nine (22.9%) HCM patients were hospitalized for non-ICU level care, and 21 (7.0%) required ICU care. Seventeen (5.6%) died: eight (2.6%) of respiratory failure, four (1.3%) of heart failure, two (0.7%) suddenly, and three (1.0%) due to other SARS-CoV-2-related complications. Covariates associated with mortality in the multivariable were age {odds ratio (OR) per 10 year increase 2.25 [95% confidence interval (CI): 1.12-4.51], P = 0.0229}, baseline New York Heart Association class [OR per one-unit increase 4.01 (95%CI: 1.75-9.20), P = 0.0011], presence of left ventricular outflow tract obstruction [OR 5.59 (95%CI: 1.16-26.92), P = 0.0317], and left ventricular systolic impairment [OR 7.72 (95%CI: 1.20-49.79), P = 0.0316]. Controlling for age and sex and comparing HCM patients with a community-based SARS-CoV-2 cohort, the presence of HCM was associated with a borderline significant increased risk of mortality OR 1.70 (95%CI: 0.98-2.91, P = 0.0600). Over one-fourth of HCM patients infected with SARS-Cov-2 required hospitalization, including 6% in an ICU setting. Age and cardiac features related to HCM, including baseline functional class, left ventricular outflow tract obstruction, and systolic impairment, conveyed increased risk of mortality

Effectiveness of a strategy that uses educational games to implement clinical practice guidelines among Spanish residents of family and community medicine (e-EDUCAGUIA project):A clinical trial by clusters

This study was funded by the Fondo de Investigaciones Sanitarias FIS Grant Number PI11/0477 ISCIII.-REDISSEC Proyecto RD12/0001/0012 AND FEDER Funding.Background: Clinical practice guidelines (CPGs) have been developed with the aim of helping health professionals, patients, and caregivers make decisions about their health care, using the best available evidence. In many cases, incorporation of these recommendations into clinical practice also implies a need for changes in routine clinical practice. Using educational games as a strategy for implementing recommendations among health professionals has been demonstrated to be effective in some studies; however, evidence is still scarce. The primary objective of this study is to assess the effectiveness of a teaching strategy for the implementation of CPGs using educational games (e-learning EDUCAGUIA) to improve knowledge and skills related to clinical decision-making by residents in family medicine. The primary objective will be evaluated at 1 and 6months after the intervention. The secondary objectives are to identify barriers and facilitators for the use of guidelines by residents of family medicine and to describe the educational strategies used by Spanish teaching units of family and community medicine to encourage implementation of CPGs. Methods/design: We propose a multicenter clinical trial with randomized allocation by clusters of family and community medicine teaching units in Spain. The sample size will be 394 residents (197 in each group), with the teaching units as the randomization unit and the residents comprising the analysis unit. For the intervention, both groups will receive an initial 1-h session on clinical practice guideline use and the usual dissemination strategy by e-mail. The intervention group (e-learning EDUCAGUIA) strategy will consist of educational games with hypothetical clinical scenarios in a virtual environment. The primary outcome will be the score obtained by the residents on evaluation questionnaires for each clinical practice guideline. Other included variables will be the sociodemographic and training variables of the residents and the teaching unit characteristics. The statistical analysis will consist of a descriptive analysis of variables and a baseline comparison of both groups. For the primary outcome analysis, an average score comparison of hypothetical scenario questionnaires between the EDUCAGUIA intervention group and the control group will be performed at 1 and 6months post-intervention, using 95% confidence intervals. A linear multilevel regression will be used to adjust the model. Discussion: The identification of effective teaching strategies will facilitate the incorporation of available knowledge into clinical practice that could eventually improve patient outcomes. The inclusion of information technologies as teaching tools permits greater learning autonomy and allows deeper instructor participation in the monitoring and supervision of residents. The long-term impact of this strategy is unknown; however, because it is aimed at professionals undergoing training and it addresses prevalent health problems, a small effect can be of great relevance. Trial registration: ClinicalTrials.gov: NCT02210442.Publisher PDFPeer reviewe