Rafael J. Villanueva

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BACKGROUND Flame cells are the terminal cells of protonephridial systems, which are part of the excretory systems of invertebrates. Although the knowledge of their biological role is incomplete, there is a consensus that these cells perform excretion/secretion activities. It has been suggested that the flame cells participate in the maintenance of the(More)
In this paper we describe epiModel, a code developed in Mathematica that facilitates the building of systems of differential equations corresponding to type-epidemiological linear or quadratic models whose characteristics are defined in text files following an easy syntax. It includes the possibility of obtaining the equations of models involving age and/or(More)
Extreme behavior is produced by small groups, but affects a large amount of people. The fear, the usual strategy of these groups, influences the decisions of the whole population. In this paper we propose a dynamical mathematical model to study the ideological evolution of the population in a region where some groups want to get political goals through(More)
Two progressive transmission procedures that are adaptive are developed, for any 3-D image which is composed from n, disjoint regions of any type. Each of the two is responsive to both the particular reconstruction process employed at the recipient node and the detail within the image. If some of the regions have already been transmitted, a next from among(More)