Héctor Jairo Martínez

In this article, we globalize the quasi-Newton algorithm proposed in Macías et al. (Appl Math Comput 441:127678, 2023) introducing an exact line search, we propose a polynomial approximation to the merit function and we deduce a sufficient condition for its minimization interval. We use the exact merit function and its approximation to propose two global quasi-Newton algorithms for solving matrix polynomial equations. For each algorithm, we prove that the exact line search does not affect the convergence of quasi-Newton method. In addition, we present comparative numerical tests of the algorithmic proposals in which we also compare with global Newton’s method.

En este trabajo plantea un modelo para la dinámica de la tuberculosis, el cual considera la población latente de bajo riesgo con el objetivo de evaluar la importancia de incluirla en el modelo y determinar si es necesario tratarla y/o controlarla. Para ello, se realizó un análisis cualitativo, determinando qué parámetros tienen mayor relevancia en la transmisión inicial de la enfermedad y calculando cuál es el número promedio de nuevas infecciones producidas por un individuo infeccioso. Se formuló y resolvió numéricamente un problema de control óptimo, en el cual se busca minimizar tanto los infectados como los costos económicos que estos impliquen la implementación de los controles en la dinámica de la tuberculosis planteada. Se utilizaron simulaciones numéricas para analizar los efectos de implementar los controles obtenidos. Por último, se realizaron simulaciones para Cali (Colombia), estableciendo una metodología para el diseño de estrategias de control para reducir la transmisión de la tuberculosis en la ciudad. This work proposes a model for the dynamics of tuberculosis, which considers a latent low-risk population, with the aim of evaluating the importance of including it in the model and determining whether it is necessary to treat and/or control it. To this effect, a qualitative analysis of the model was carried out, determining which parameters are most relevant in the initial transmission of the disease and calculating the average number of new infections produced by an infectious individual. An optimal control problem was formulated and numerically solved, which seeks to minimize both the infected and the economic costs generated by the implementation of controls in the proposed dynamics of tuberculosis. Numerical simulations were used to analyze the effects of implementing the controls obtained. Finally, simulations are carried out for Cali (Colombia), establishing a methodology for the design of control strategies aimed at reducing the transmission of tuberculosis in the city.

Over the last decade, the release of Wolbachia-infected Aedes aegypti into the natural habitat of this mosquito species has become the most sustainable and long-lasting technique to prevent and control vector-borne diseases, such as dengue, zika, or chikungunya. However, the limited resources to generate such mosquitoes and their effective distribution in large areas dominated by the Aedes aegypti vector represent a challenge for policymakers. Here, we introduce a mathematical framework for the spread of dengue in which competition between wild and Wolbachia-infected mosquitoes, the cross-contagion patterns between humans and vectors, the heterogeneous distribution of the human population in different areas, and the mobility flows between them are combined. Our framework allows us to identify the most effective areas for the release of Wolbachia-infected mosquitoes to achieve a large decrease in the global dengue prevalence.

En este artículo, proponemos un nuevo algoritmo tipo Newton inexacto para resolver el problema de complementariedad horizontal mediante su reformulación como un problema de minimización restricto. El algoritmo usa la estrategia de combinar una dirección Newton inexacta con su proyección sobre el conjunto factible; esta última opción solo se usa cuando se necesita garantizar factibilidad. Además, presentamos un análisis teórico y numérico del nuevo algoritmo.

This paper focuses on the design and analysis of short-term control intervention measures seeking to suppress local populations of Aedes aegypti mosquitoes, the major transmitters of dengue and other vector-borne infections. Besides traditional measures involving the spraying of larvicides and/or insecticides, we include biological control based on the deliberate introduction of predacious species feeding on the aquatic stages of mosquitoes. From the methodological standpoint, our study relies on application of the optimal control modeling framework in combination with the cost-effectiveness analysis. This approach not only enables the design of optimal strategies for external control intervention but also allows for assessment of their performance in terms of the cost-benefit relationship. By examining numerous scenarios derived from combinations of chemical and biological control measures, we try to find out whether the presence of predacious species at the mosquito breeding sites may (partially) replace the common practices of larvicide/insecticide spraying and thus reduce their negative impact on non-target organisms. As a result, we identify two strategies exhibiting the best metrics of cost-effectiveness and provide some useful insights for their possible implementation in practical settings.