ANALISIS COMPARATIVO DEL DESEMPEÑO DE LOS ALGORITMOS FSD Y QRD-M EN SISTEMAS MIMO 4X4

Los sistemas de comunicaciones de Múltiples Entradas y Múltiples Salidas (MIMO, Multiple-Input Multiple-Output) son uno de los pilares de las altas capacidades de transmisión de datos, ofrecidas por los sistemas de comunicación de tercera y cuarta generación. Una de sus etapas más críticas es el proceso de detección, por ello este artículo presenta un análisis comparativo del desempeño de los algoritmos Decodifcador Esférico de Complejidad Fija (FSD, Fixed-complexity Sphere Decoder) y Descomposición QR con M-algoritmos (QRD-M, QR Decomposition-M), empleados en la detección en sistemas MIMO. Para ello se realiza un estudio detallado de las generalidades del sistema MIMO, y se sigue una metodología que permite abordar el problema de la detección, desde una concepción analítica para después modelarlo en un sistema computacional. Los sistemas MIMO cuentan con múltiples antenas de transmisión y recepción, estos emplean esquemas de multiplexación para mejorar la comunicación, con el inconveniente de que los símbolos se interferen en el receptor, por lo que se requieren algoritmos de detección de señales que permitan detectar los símbolos enviados, entre los cuales se encuentran los algoritmos FSD y QRD-M, estos son analizados y simulados en Matlab para comparar su desempeño, con el fn de determinar el algoritmo adecuado a implementar en un sistema MIMO determinado. En la metodología para el desarrollo de la simulación, se defnen los parámetros de los algoritmos, el diagrama de bloques del sistema y los escenarios de simulación, para así realizar el análisis de desempeño. En el análisis de los resultados, los algoritmos FSD y QRD-M se comparan con el algoritmo Máxima Verosimilitud (ML, Maximum Likelihood), el desempeño se determina mediante la comparación de las curvas de Tasa de Error de Bit (BER, Bit Error Rate) vs. Relación Señal a Ruido (SNR, Signal to Noise Ratio) y la complejidad computacional de cada algoritmo

Early Risk Factors for Obesity in the First 1000 Days-Relationship with Body Fat and BMI at 2 Years

Background: Obesity is defined as an excessive accumulation of body fat. Several early developmental factors have been identified which are associated with an increased risk of childhood obesity and increased adiposity in childhood. The primary objective of the present study is to analyse the effect of various early risk factors on Body Mass Index (BMI) and body fat percentage at 2 years of age. (2) Methods: A prospective cohort study design was used, with the sample consisting of 109 mother-child pairs from whom data were collected between early pregnancy and 2 years old. Adiposity was determined based on skinfold measurements using the Brooks and Siri formulae. Mean comparison tests (Student's t-test and ANOVAs) and multiple linear regression models were used to analyse the relationship between early programming factors and dependent variables. (3) Results: Maternal excess weight during early pregnancy (beta = 0.203, p = 0.026), gestational smoking (beta = 0.192, p = 0.036), and accelerated weight gain in the first 2 years (beta = - 0.269, p = 0.004) were significantly associated with high body fat percentage. Pre-pregnancy BMI and accelerated weight gain in the first 2 years were associated with high BMI z-score (beta = 0.174, p = 0.047 and beta = 0.417, p = 0.000 respectively). The cumulative effect of these variables resulted in high values compared to the baseline zero-factor group, with significant differences in BMI z-score (F = 8.640, p = 0.000) and body fat percentage (F = 5.402, p = 0.002) when three factors were present. (4) Conclusions: The presence of several early risk factors related to obesity in infancy was significantly associated with higher BMI z-score and body fat percentage at 2 years of age. The presence of more than one of these variables was also associated with higher adiposity at 2 years of age. Early prevention strategies should address as many of these factors as possible.This study was supported by public funds, the ITI call (integrated territorial investment), developed by the Health Department of the Andalusian Government. The project has been 80% co-financed by funds from the FEDER operational program of Andalusia 2014-2020. Documen

Influence of high cardiovascular risk in asymptomatic people on the duration and cost of sick leave: results of the ICARIA study.

AIMS: We investigated the potential influence of a moderate-to-high cardiovascular (CV) risk (CVR) (defined as a Systematic COronary Risk Evaluation model, or SCORE ≥ 4%), in the absence of an established CV disease, on the duration and cost of CV and non-CV sick leave (SL) resulting from common and occupational accidents or diseases. METHODS AND RESULTS: We conducted a prospective cohort study on 690 135 workers with a 1-year follow-up and examined CV- and non-CV-related SL episodes. To obtain baseline values, CVR factors were initially assessed at the beginning of the year during routine medical examination. The CVR was calculated with the SCORE charts for all subjects. Moderate-to-high CVR was defined as SCORE ≥ 4%. A baseline SCORE ≥ 4% was associated with a higher risk for long-term CV and non-CV SL, as revealed by follow-up assessment. This translated into an increased cost, estimated at euro5 801 464.18 per year. Furthermore, pharmacological treatment for hypertension or hyperlipidaemia was significantly associated with longer SL duration. CONCLUSION: Moderate-to-high CVR in asymptomatic subjects was significantly associated with the duration and cost of CV and non-CV SL. These results constitute the first body of evidence that the SCORE charts can be used to identify people with a non-established CV disease, which might ultimately translate into more lost workdays and therefore increased cost for society

Código Cáncer: resultados preliminares

Antecedentes: Los retrasos en la atención de personas con cáncer impactan negativamente su calidad de vida y aumentan los costos al sistema de salud. / Objetivo: Describir las fases del proyecto Código Cáncer y sus resultados preliminares. / Métodos: Se organizaron siete grupos de investigación para: a) entender las causas de los retrasos que enfrentan las personas con cáncer en México, sus trayectorias y costos asociados; b) conocer los mecanismos de referencia formales e informales que constituyen su trayectoria en el sistema de salud, y c) entender la infraestructura existente y la necesaria para responder a las necesidades epidemiológicas del país. / Resultados: Estos resultados sientan las bases para la implementación de un programa de referencia rápida de pacientes. / Conclusión: Las políticas de diagnóstico y tratamiento oportuno del cáncer basadas en la evidencia son imprescindibles para atender los retrasos en la atención. Código Cáncer representa un proyecto innovador para lograr este objetivo en México

Predicting the onset of anxiety syndromes at 12 months in primary care attendees. The PredictA-Spain study

Background: There are no risk algorithms for the onset of anxiety syndromes at 12 months in primary care. We aimed to develop and validate internally a risk algorithm to predict the onset of anxiety syndromes at 12 months. Methods: A prospective cohort study with evaluations at baseline, 6 and 12 months. We measured 39 known risk factors and used multilevel logistic regression and inverse probability weighting to build the risk algorithm. Our main outcome was generalized anxiety, panic and other non-specific anxiety syndromes as measured by the Primary Care Evaluation of Mental Disorders, Patient Health Questionnaire (PRIME-MD-PHQ). We recruited 3,564 adult primary care attendees without anxiety syndromes from 174 family physicians and 32 health centers in 6 Spanish provinces. Results: The cumulative 12-month incidence of anxiety syndromes was 12.2%. The predictA-Spain risk algorithm included the following predictors of anxiety syndromes: province; sex (female); younger age; taking medicines for anxiety, depression or stress; worse physical and mental quality of life (SF-12); dissatisfaction with paid and unpaid work; perception of financial strain; and the interactions sex*age, sex*perception of financial strain, and age*dissatisfaction with paid work. The C-index was 0.80 (95% confidence interval = 0.78–0.83) and the Hedges' g = 1.17 (95% confidence interval = 1.04–1.29). The Copas shrinkage factor was 0.98 and calibration plots showed an accurate goodness of fit. Conclusions: The predictA-Spain risk algorithm is valid to predict anxiety syndromes at 12 months. Although external validation is required, the predictA-Spain is available for use as a predictive tool in the prevention of anxiety syndromes in primary care.This study was supported by the Spanish Ministry of Health (grant FIS references: PI041980, PI041771, PI042450 and PI06/1442) and the Andalusian Council of Health (grant references: 05/403 and 06/278); as well as the Spanish Network of Primary Care Research ‘redIAPP’ (RD06/0018), the ‘Aragón group’ (RD06/0018/0020), the ‘Baleares group’ (RD07/0018/0033), and the ‘SAMSERAP group’ (RD06/0018/0039)

Predicting the onset and persistence of episodes of depression in primary health care. The predictD-Spain study: Methodology

Background: The effects of putative risk factors on the onset and/or persistence of depression remain unclear. We aim to develop comprehensive models to predict the onset and persistence of episodes of depression in primary care. Here we explain the general methodology of the predictD-Spain study and evaluate the reliability of the questionnaires used. Methods: This is a prospective cohort study. A systematic random sample of general practice attendees aged 18 to 75 has been recruited in seven Spanish provinces. Depression is being measured with the CIDI at baseline, and at 6, 12, 24 and 36 months. A set of individual, environmental, genetic, professional and organizational risk factors are to be assessed at each follow-up point. In a separate reliability study, a proportional random sample of 401 participants completed the test-retest (251 researcher-administered and 150 self-administered) between October 2005 and February 2006. We have also checked 118,398 items for data entry from a random sample of 480 patients stratified by province. Results: All items and questionnaires had good test-retest reliability for both methods of administration, except for the use of recreational drugs over the previous six months. Cronbach's alphas were good and their factorial analyses coherent for the three scales evaluated (social support from family and friends, dissatisfaction with paid work, and dissatisfaction with unpaid work). There were 191 (0.16%) data entry errors. Conclusion: The items and questionnaires were reliable and data quality control was excellent. When we eventually obtain our risk index for the onset and persistence of depression, we will be able to determine the individual risk of each patient evaluated in primary health care.The research in Spain was funded by grants from the Spanish Ministry of Health (grant FIS references: PI04/1980, PI0/41771, PI04/2450, and PI06/1442), Andalusian Council of Health (grant references: 05/403, 06/278 and 08/0194), and the Spanish Ministry of Education and Science (grant reference SAF 2006/07192). The Malaga sample, as part of the predictD-International study, was also funded by a grant from The European Commission (reference QL4-CT2002-00683)

Guía de práctica clínica para la prevención, diagnóstico, tratamiento y rehabilitación de la falla cardiaca en población mayor de 18 años, clasificación B, C y D

La falla cardíaca es un síndrome clínico caracterizado por síntomas y signos típicos de insuficiencia cardíaca, adicional a la evidencia objetiva de una anomalía estructural o funcional del corazón. Guía completa 2016. Guía No. 53Población mayor de 18 añosN/