A Second-Order Method for the Numerical Integration of a Size-Structured Cell Population Model

Producción CientíficaWe consider the numerical integration of a size-structured cell population model. We propose a new second-order numerical method to attain its solution. The scheme is analyzed and the optimal rate of convergence is derived. We show experimentally the predicted accuracy of the scheme.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA191U13

A second-order numerical method for a cell population model with asymmetric division

Producción CientíficaPopulation balance models represent an accurate and general way of describing the complicated dynamics of cell growth. In this paper we study the numerical integration of a model for the evolution of a size-structured cell population with asymmetric division. We present and analyze a novel and efficient second-order numerical method based on the integration along the characteristic curves. We prove the optimal rate of convergence of the scheme andweratify it by numerical simulation. Finally,weshow that the numerical scheme serves as a valuable tool in order to approximate the stable size distribution of the model.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA191U13

Study on the efficiency in the numerical integration of size-structured population models: Error and computational cost

Producción CientíficaWe describe a procedure which is useful to select an appropriate numerical method in a size-structured population model. We consider four different numerical methods based on finite difference schemes or characteristics curves integration. We compute an analytical approximation in terms of the discretization parameters for the theoretical error principal terms and the computational cost. Thus, we show the efficiency curve that allows to select the best relationship between the discretization parameters for each numerical method. Finally, we obtain the most efficient numerical method for each test.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA191U13

Analysis of an efficient integrator for a size-structured population model with a dynamical resource

Producción CientíficaIn this paper, an efficient numerical method for the approximation of a nonlinear size-structured population model is presented. The nonlinearity of the model is given by dependency on the environment through the consumption of a dynamical resource. We analyse the properties of the numerical scheme and optimal second-order convergence is derived. We report experiments with academical tests to demonstrate numerically the predicted accuracy of the scheme. The model is applied to solve a biological problem: the dynamics of an ectothermic population (the water flea, Daphnia magna). We analyse its long time evolution and describe the asymptotically stable steady states, both equilibria and limit cycles.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA191U13

Numerical Analysis of a Size-Structured Population Model with a Dynamical Resource

Producción CientíficaIn this paper, we analyze the convergence of a second-order numerical method for the approximation of a size-structured population model whose dependency on the environment is managed by the evolution of a vital resource. Optimal convergence rate is derived. Numerical experiments are also reported to demonstrate the predicted accuracy of the scheme. Also, it is applied to solve a problem that describes the dynamics of a Daphnia magna population, paying attention to the unstable case.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA191U13

The Potential of Seaweeds as a Source of Functional Ingredients of Prebiotic and Antioxidant Value

Two thirds of the world is covered by oceans, whose upper layer is inhabited by algae. This means that there is a large extension to obtain these photoautotrophic organisms. Algae have undergone a boom in recent years, with consequent discoveries and advances in this field. Algae are not only of high ecological value but also of great economic importance. Possible applications of algae are very diverse and include anti-biofilm activity, production of biofuels, bioremediation, as fertilizer, as fish feed, as food or food ingredients, in pharmacology (since they show antioxidant or contraceptive activities), in cosmeceutical formulation, and in such other applications as filters or for obtaining minerals. In this context, algae as food can be of help to maintain or even improve human health, and there is a growing interest in new products called functional foods, which can promote such a healthy state. Therefore, in this search, one of the main areas of research is the extraction and characterization of new natural ingredients with biological activity (e.g., prebiotic and antioxidant) that can contribute to consumers? well-being. The present review shows the results of a bibliographic survey on the chemical composition of macroalgae, together with a critical discussion about their potential as natural sources of new functional ingredients.Fil: Gomez Zavaglia, Andrea. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Prieto Lage, Miguel Ángel. Universidad de Vigo; EspañaFil: Jiménez López, Cecilia. Universidad de Vigo.; EspañaFil: Mejuto, Juan Carlos. Universidad de Vigo. Facultad de Ciencias de Ourense; EspañaFil: Simal Gándara, Jesús. Universidad de Vigo; Españ

An age-structured population model with delayed and space-limited recruitment

Producción CientíficaA new age-structured model for a closed population with space-limited recruitment is proposed. The problem incorporates a time delay in the settlement process representing, for a marine population of invertebrates, the pelagic larval phase previous to the sessile stage. The model possesses a nontrivial steady state which is investigated. For a deeper analysis of the stability of this equilibrium, depending on the delay, an appropriate numerical method is proposed. The nontrivial equilibrium of the numerical scheme, based on the representation of the solution along the characteristics lines, is also analyzed. For a test model associated with the dynamics of a population of barnacles, numerical experiments describing the asymptotic behavior of the solutions varying the delay are provided. In this case, the delay behaves as a destabilizing parameter of the dynamics of the model.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (grant MTM2017- 85476-C2-1-P)Agencia Estatal de Investigación (grant PID2020-113554GB-I00/AEI/10.13039/501100011033)Junta de Castilla y León - Fondo Europeo de Desarrollo Regional (project VA193P20

Numerical integration of a hierarchically size-structured population model with contest competition

Producción CientíficaWe formulate schemes for the numerical solution to a hierarchically size-structured population model. The schemes are analysed and optimal rates of convergence are derived. Some numerical experiments are also reported to demonstrate the predicted accuracy of the schemes and to show their behaviour to approaching stable steady states.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA191U13

Telecommuting´s impact in management and communications variables: IT sector case

En este artículo vamos a profundizar en el análisis de las asociaciones existentes entre las diferentes modalidades de teletrabajo que se encuentran en el sector de TIC y las variables relacionadas con la dirección y comunicación. Por un lado, abundaremos en la forma en que se controla el rendimiento de los teletrabajadores, el momento en que se realiza el control y, en este punto, si son los mismos que se aplican a los no teletrabajadores. También, trataremos de conocer las diferencias respecto a la opinión de si la supervisión de los teletrabajadores requiere más tiempo que la de sus compañeros y al grado de autonomía de éstos para tomar decisiones. Por otro, puntualizaremos las posibles diferencias encontradas respecto a la influencia que tiene el teletrabajo sobre algunas de las variables de comunicación y sobre las opiniones relacionadas con la efectividad de las comunicaciones con los teletrabajadores, características de la dirección remota o el modo de entender la labor del supervisor.In this article we are going to deepen in the analysis of the existing associations between the different modalities from telecommuting in the sector of CIT and variables related to the direction and communication patterns. On the one hand, we will abound in the form at that controls the results of telecommuters, the moment in which the control is made and, in this point, if they are the same that they are applied to non-telecommuters. Also, we will try to know the differences with respect to the opinion of if the supervision of telecommuters requires more time than the one of colleagues and the degree of autonomy of them to make decisions. On the other hand, we will emphasize the possible differences found with respect to the influence that has telecommuting on some of the communication variables and the opinions related to the effectiveness of the communications with the teleworkers, characteristics of the remote direction or the way to understand the work of the supervisor

Numerical analysis of a cell dwarfism model

Producción CientíficaIn this work, we study numerically a model which describes cell dwarfism. It consists in a pure initial value problem for a first order partial differential equation, that can be applied to the description of the evolution of diseases as thalassemia. We design two numerical methods that prevent the use of the characteristic curve x = 0, and derive their optimal rates of convergence. Numerical experiments are also reported in order to demonstrate the predicted accuracy of the schemes. Finally, a comparison study on their efficiency is presented.Junta de Castilla y León and European FEDER Funds (VA041P17)Junta de Castilla y León (VA138G18)Ministerio de Economía, Industria y Competitividad and European FEDER Funds (Project MTM2014-56022-C2-2-P)Ministerio de Ciencia e Innovación (Proyect MTM2017-85476-C2-P