9 research outputs found

    Robust control of pH in a raceway photobiorreactor

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    [EN] This work presents a first approach to the robust control of pH in a raceway photobioreactor for the cultivation of microalgae. In this type of process, pH is the most critical variable to control, having a direct relationship with the productivity of the system. The dynamics of the pH has a strongly non-linear character, being affected by numerous factors such as the contribution of CO2 to the culture medium or the performance of photosynthesis by the microalgae. This non-linearity generates a great source of uncertainty in the process even when the system is controlled around the desired operating point. Therefore, in this article we have proceeded to model the system with parametric uncertainty covering the typical working ranges of pH, and later a robust controller with QFT is designed to achieve certain robust performance and stability requirements. The resulting control algorithm has been evaluated in simulation and in real tests against different working conditions and at different operating points, obtaining satisfactory results. [ES] Este  trabajo  presenta  una  primera  aproximación al control robusto del pH en un fotobiorreactor raceway  para  el  cultivo  de  microalgas. En este tipo de procesos el pH es la variable más crítica a controlar teniendo una relación directa con la productividad del sistema. La dinámica del pH posee un carácter fuertemente no lineal estando afectada por numerosos factores tales como el aporte del CO2 al medio de cultivo o la realización de la fotosíntesis por parte de las microalgas. Esta no linealidad genera una gran fuente de incertidumbre en el proceso incluso cuando el sistema es controlado alrededor del punto de operación deseado. Por tanto, en este artículo se ha procedido a realizar el modelado del sistema con incertidumbre paramétrica cubriendo los rangos de trabajo típicos del pH, y posteriormente se ha realizado el diseño de un controlador robusto con la técnica Quantitative Feedback Theory (QFT) para conseguir unos requisitos de rendimiento y estabilidad robustos determinados. El algoritmo de control resultante se ha evaluado en simulación y mediante ensayos reales frente a distintas condiciones de trabajo y en distintos puntos de operación, obteniéndose resultados satisfactorios.Esta publicacion es parte de los proyectos de I +D+i PID2020-112709RB-C21 y PID2020-112709RB-C22, financiado por el Ministerio de Ciencia e Innovación y FEDER “Una manera de hacer Europa”.Hoyo Sánchez, Á.; Guzmán Sánchez, JL.; Moreno Úbeda, JC.; Baños Torrico, A. (2022). Control robusto del pH en un fotobiorreactor raceway. Revista Iberoamericana de Automática e Informática industrial. 19(3):274-283. https://doi.org/10.4995/riai.2022.16731OJS27428319

    Role of age and comorbidities in mortality of patients with infective endocarditis

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    [Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

    Primer consenso colombiano sobre Chagas congénito y orientación clínica a mujeres en edad fértil con diagnóstico de Chagas

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    ResumenLa transmisión congénita de la enfermedad de Chagas ha sido poco estudiada en Colombia y existen pocos procedimientos rutinarios en el sistema de salud para el manejo de esta enfermedad. Por ello se desarrolló un consenso de expertos dirigido a generar recomendaciones de diagnóstico y tratamiento de Chagas congénito y orientación a mujeres en edad fértil. Con ese propósito se realizó una búsqueda extensiva de la literatura, empleando una combinación de términos MeSH (Chagas, Chagas congénito, prevención, control, diagnóstico, tratamiento y embarazo) para reflejar el estado del arte en cada tema de interés. Después de ello, se leyeron los resúmenes y aquellos seleccionados para análisis del texto completo. La literatura relevante se sintetizó, clasificó y organizó en tablas y se presentó al panel de expertos, el cual estaba constituido por 30 profesionales en diferentes áreas. Mediante la metodología Delphi se realizaron 2 rondas de cuestionarios virtuales y una reunión presencial en los cuales se evaluaron los niveles de acuerdo entre los participantes. Los puntos con falta de consenso durante las 2 rondas virtuales se expusieron durante las mesas de discusión en la ronda presencial. La evidencia utilizada se adaptó a las particularidades nacionales según el caso y se aprobó el contenido del documento final. Se propone que estas recomendaciones sean usadas por profesionales de la salud en Colombia.AbstractCongenital transmission of Chagas disease has not been extensively studied in Colombia, and there are no standardized processes in the health system regarding the specific diagnosis, treatment and follow-up of this disease. In order to generate recommendations on congenital Chagas disease and Chagas in women of childbearing age in Colombia, a consensus of experts was developed. An extensive literature search through the Medline database was carried out using the MeSH terms: «Chagas disease/congenital», «prevention and control», «diagnosis», «therapeutics» and «pregnancy». Appropriate abstracts were selected and the full texts were analyzed. The relevant information was synthesized, classified, and organized into tables and figures and was presented to a panel of experts, which was composed of 30 professionals from various fields. Based on the Delphi methodology, three rounds of consultation were conducted. The first and second rounds were based on electronic questionnaires that measured the level of consensus of each question among the participants. The third round was based on a face-to-face discussion focusing on those questions without consensus in the previous consultations. The evidence was adapted to national circumstances on a case-by-case basis, and the content the final document was approved. These recommendations are proposed for use in routine medical practice by health professionals in Colombia

    Primer consenso colombiano sobre Chagas congénito y orientación clínica a mujeres en edad fértil con diagnóstico de Chagas

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    La transmisión congénita de la enfermedad de Chagas ha sido poco estudiada en Colombia y existen pocos procedimientos rutinarios en el sistema de salud para el manejo de esta enfermedad. Por ello se desarrolló un consenso de expertos dirigido a generar recomendaciones de diagnóstico y tratamiento de Chagas congénito y orientación a mujeres en edad fértil. Con ese propósito se realizó una búsqueda extensiva de la literatura, empleando una combinación de términos MeSH (Chagas, Chagas congénito, prevención, control, diagnóstico, tratamiento y embarazo) para reflejar el estado del arte en cada tema de interés. Después de ello, se leyeron los resúmenes y aquellos seleccionados para análisis del texto completo. La literatura relevante se sintetizó, clasificó y organizó en tablas y se presentó al panel de expertos, el cual estaba constituido por 30 profesionales en diferentes áreas. Mediante la metodología Delphi se realizaron 2 rondas de cuestionarios virtuales y una reunión presencial en los cuales se evaluaron los niveles de acuerdo entre los participantes. Los puntos con falta de consenso durante las 2 rondas virtuales se expusieron durante las mesas de discusión en la ronda presencial. La evidencia utilizada se adaptó a las particularidades nacionales según el caso y se aprobó el contenido del documento final. Se propone que estas recomendaciones sean usadas por profesionales de la salud en Colombia

    Prosthetic Valve Candida spp. Endocarditis: New Insights Into Long-term Prognosis—The ESCAPE Study

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    International audienceBackground: Prosthetic valve endocarditis caused by Candida spp. (PVE-C) is rare and devastating, with international guidelines based on expert recommendations supporting the combination of surgery and subsequent azole treatment.Methods: We retrospectively analyzed PVE-C cases collected in Spain and France between 2001 and 2015, with a focus on management and outcome.Results: Forty-six cases were followed up for a median of 9 months. Twenty-two patients (48%) had a history of endocarditis, 30 cases (65%) were nosocomial or healthcare related, and 9 (20%) patients were intravenous drug users. "Induction" therapy consisted mainly of liposomal amphotericin B (L-amB)-based (n = 21) or echinocandin-based therapy (n = 13). Overall, 19 patients (41%) were operated on. Patients <66 years old and without cardiac failure were more likely to undergo cardiac surgery (adjusted odds ratios [aORs], 6.80 [95% confidence interval [CI], 1.59-29.13] and 10.92 [1.15-104.06], respectively). Surgery was not associated with better survival rates at 6 months. Patients who received L-amB alone had a better 6-month survival rate than those who received an echinocandin alone (aOR, 13.52; 95% CI, 1.03-838.10). "Maintenance" fluconazole therapy, prescribed in 21 patients for a median duration of 13 months (range, 2-84 months), led to minor adverse effects.Conclusion: L-amB induction treatment improves survival in patients with PVE-C. Medical treatment followed by long-term maintenance fluconazole may be the best treatment option for frail patients

    Role of age and comorbidities in mortality of patients with infective endocarditis.

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    The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups: A total of 3120 patients with IE (1327  There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in th

    Infective Endocarditis in Patients With Bicuspid Aortic Valve or Mitral Valve Prolapse

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    Contemporary use of cefazolin for MSSA infective endocarditis: analysis of a national prospective cohort

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    Objectives: This study aimed to assess the real use of cefazolin for methicillin-susceptible Staphylococcus aureus (MSSA) infective endocarditis (IE) in the Spanish National Endocarditis Database (GAMES) and to compare it with antistaphylococcal penicillin (ASP). Methods: Prospective cohort study with retrospective analysis of a cohort of MSSA IE treated with cloxacillin and/or cefazolin. Outcomes assessed were relapse; intra-hospital, overall, and endocarditis-related mortality; and adverse events. Risk of renal toxicity with each treatment was evaluated separately. Results: We included 631 IE episodes caused by MSSA treated with cloxacillin and/or cefazolin. Antibiotic treatment was cloxacillin, cefazolin, or both in 537 (85%), 57 (9%), and 37 (6%) episodes, respectively. Patients treated with cefazolin had significantly higher rates of comorbidities (median Charlson Index 7, P <0.01) and previous renal failure (57.9%, P <0.01). Patients treated with cloxacillin presented higher rates of septic shock (25%, P = 0.033) and new-onset or worsening renal failure (47.3%, P = 0.024) with significantly higher rates of in-hospital mortality (38.5%, P = 0.017). One-year IE-related mortality and rate of relapses were similar between treatment groups. None of the treatments were identified as risk or protective factors. Conclusion: Our results suggest that cefazolin is a valuable option for the treatment of MSSA IE, without differences in 1-year mortality or relapses compared with cloxacillin, and might be considered equally effective

    Mural Endocarditis: The GAMES Registry Series and Review of the Literature

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