18 research outputs found

    Reactive scheduling to treat disruptive events in the MRCPSP

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    Esta tesis se centra en diseñar y desarrollar una metodología para abordar el MRCPSP con diversas funciones objetivo y diferentes tipos de interrupciones. En esta tesis se exploran el MRCPSP con dos funciones objetivo, a saber: (1) minimizar la duración del proyecto y (2) maximizar el valor presente neto del proyecto. Luego, se tiene en cuenta dos tipos diferentes de interrupciones, (a) interrupción de duración, e (b) interrupción de recurso renovable. Para resolver el MRCPSP, en esta tesis se proponen tres estrategias metaheurísticas: (1) algoritmo memético para minimizar la duración del proyecto, (2) algoritmo adaptativo de forrajeo bacteriano para maximizar el valor presente neto del proyecto y (3) algoritmo de optimización multiobjetivo de forrajeo bacteriano (MBFO) para resolver el MRCPSP con eventos de interrupción. Para juzgar el rendimiento del algoritmo memético y de forrajeo bacteriano propuestos, se ha llevado a cabo un extenso análisis basado en diseño factorial y diseño Taguchi para controlar y optimizar los parámetros del algoritmo. Además se han puesto a prueba resolviendo las instancias de los conjuntos más importantes en la literatura: PSPLIB (10,12,14,16,18,20 y 30 actividades) y MMLIB (50 y 100 actividades). También se ha demostrado la superioridad de los algoritmos metaheurísticos propuestos sobre otros enfoques heurísticos y metaheurísticos del estado del arte. A partir de los estudios experimentales se ha ajustado la MBFO, utilizando un caso de estudio.DoctoradoDoctor en Ingeniería Industria

    Algoritmo memético para resolver el problema de secuenciación con recursos limitados modo múltiple, MRCPSP

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    El objetivo de esté documento es desarrollar e implementar en C++ un algoritmo memético para resolver el MRCPSP. Este algoritmo utiliza componentes de los algoritmos genéticos y búsqueda de vecindarios variables. Se implementa una adaptación del operador de cruce uniforme para el MRCPSP y una búsqueda local VNS de manera que genere mejores soluciones. Se utiliza una función de evaluación de los agentes que guía adecuadamente la evolución del algoritmo. La propuesta realizada para resolver el MRCPSP se ha implementado y sus resultados se han evaluado mediante la solución de las instancias de la librería estándar PSPLIBMaestríaMagister en Matemática

    Deliverología en la capacidad de cumplimiento en la atención prioritaria del área crítica Río Santiago

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    La investigación tiene como objetivo principal evaluar los factores que han limitado la eficacia de la intervención interinstitucional que articula, monitorea y evalúa el Consejo Nacional de Fronteras e Integración Fronteriza (Conadif) en el área crítica de frontera del río Santiago, de la provincia de Condorcanqui, departamento de Amazonas, durante el periodo 2013-2017, y que sirvan de base para la determinación de una propuesta de mejora de la intervención interinstitucional mediante la articulación gubernamental que establece la deliverología. En ese sentido, el estudio generó tres aportes importantes: el diagnóstico cuantitativo de dicha intervención, su evaluación metodológica y sus propuestas de mejora a la luz de la deliverología. La justificación principal de la investigación se centra en el hecho de que recientemente fueron incorporadas nuevas competencias a este organismo sin considerar una evaluación a su desempeño como articulador. En efecto, las disposiciones del Poder Ejecutivo del primer semestre de 2018 relacionadas con la implementación de la política nacional de desarrollo e integración fronteriza no solo buscan potenciar las competencias originales del Conadif, otorgadas cinco años atrás, sino también le incorporan otras nuevas mediante la definición de acciones de atención prioritaria para las áreas críticas de frontera

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    O Brasil e o Grão Caribe: fundamentos para uma nova agenda de trabalho Brazil and the Great Caribbean basin: the making of a new agenda

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    O artigo aborda as relações econômicas, políticas e de segurança internacional vigentes entre o Brasil e os 25 países da bacia do Caribe - México, América Central, Antilhas, Colômbia, Venezuela, Guiana e Suriname, além de uma dezena de territórios coloniais administrados por potências extra-regionais. Constata-se que as relações econômicas são muito intensas, especialmente em termos comerciais e de investimentos produtivos. O diálogo político entre as partes é construtivo, relevante e cada vez mais significativo. No que diz respeito às questões de segurança, vale destacar suas convergências, bem como certas divergências de natureza geopolítica derivadas do projeto brasileiro para a América do Sul. No final do artigo, propõem-se três cenários plausíveis para o futuro das relações entre Brasil e Caribe.<br>The paper explores the economic, political and security relations between Brazil and the 25 Caribbean countries - Mexico, Central America, the Caribbean islands, Colombia, Venezuela, Guiana and Suriname, inasmuch the colonial territories. The text suggest that the economic relations are very intensive. The political dialogue is constructive. In the security field, there are some convergences and divergences derived from the brazilian=s South American project. At the end, the paper consider three reasonable scenarios for the Brazilian-Caribbean relations

    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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    Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

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    International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora
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