https://repositorio.utem.cl/handle/30081993/1363 Sat, 04 Apr 2026 11:28:11 GMT 2026-04-04T11:28:11Z https://repositorio.utem.cl/handle/30081993/1380 The complex and systemic establishment of interactions in the ecological communities. Veloz, Tomas; Ramirez, Claudio C. The central question in community ecology is explaining how species coexist in a ecological community. In this tradition, individuals belonging to species constitute the biological unit on which observations are concentrated. Individuals produce interactions, and the interactions depend on the individuals. Thus, the individual/population duality and the resulting interactions between these entities are the structuring forces, and the abiotic environment is the conditioning space that, by affecting individuals, becomes another structuring factor. Thus, ecological interactions among individuals in a community emerge as secondary entities resulting as the mere consequence of the properties of individuals (e.g., feeding, fighting, reproduction), and the set of key interactions are candidates for primary causes of community structuring. The modeling of ecological communities is done either by describing their interactions as terms of a dynamical system, links of a network, or rules in agent-based model. However, none of these frameworks can simultaneously i) handle large size systems, while ii) describing interaction mechanisms in detail, and iii) providing ways to compare different models not only based on dynamical results. Here we review the features of these modeling frameworks and introduce the language of reaction networks, native to systems biology, as an alternative method where these three features can be simultaneously achieved. Reaction networks require a paradigm shift as features of species and abiotic environment have the same importance, and the focus is not on the species interactions themselves, but on more general processes of exchange of conditions for the persistence of the whole community. Pág. 27 – 33, esquemas, tablas. Thu, 01 Dec 2022 00:00:00 GMT https://repositorio.utem.cl/handle/30081993/1380 2022-12-01T00:00:00Z https://repositorio.utem.cl/handle/30081993/1379 Respuesta Lombard Frente a Ruidos Antropogénicos Cuasiperiódicos: Una propuesta teórica-matemática. Ramirez-Carrasco, Carlos Noise is a form of pollution resulting from the undeniable increase in industrialization worldwide. Anthropogenic noise can have negative effects on the survival of a species, as it can mask acoustic signals relevant to foraging, mate searching and distribution. In response to this, the Lombard effect acts as a compensatory mechanism, and refers to an increase in the amplitude of acoustic signals in response to an increase in background noise level. In this study, a theoretical-mathematical approach is proposed to illustrate a simple classification based on three general types of Lombard response. Finally, by means of numerical simulations, we graphically analyze the effects of Lombard responses in a mathematical model of population persistence in a critical and quasi-periodic noise environment. Pág. 19 – 25, gráficos, fórmulas. Thu, 01 Dec 2022 00:00:00 GMT https://repositorio.utem.cl/handle/30081993/1379 2022-12-01T00:00:00Z https://repositorio.utem.cl/handle/30081993/1378 De las redes de reacciones al surgimiento del metabolismo. Becerra, Diego Living systems are instances of far-from-equilibrium dissipative structures. Several theories about their origin have been proposed, but they are hard to test empirically. One promising strategy is to search the minimal biosynthetic core common to the most ancestral unicellular organisms (e.g. acetogenic bacteria and methanogenic archaea), and to test whether the chemical species from the core are present in candidate scenarios for the origin of life, and whether the reactions are thermodynamically favorable, autocatalytic, dynamically stable, etc. Chemical Organization Theory, a mathematical framework which allow us to represent and compute the set of all possible observable configurations from a given reaction network, can be used to test hypotheses in silico about molecular self-organization prior to the first metabolic network withing a living system. In order to do this, the theory will be introduced, and a thermodynamically favorable biosynthetic network will be analyzed with Chemical Organization Theory’ tools. Organizations containing the inflow species from the biosynthetic core (H2,CO2,NH3,Pi ,H2O, and H2S) plus formate, FeS clusters, bicarbonate, CO, and H + were found. Hydrothermal Alkaline Vents, a strong candidate for the origin of life, contains the set of species found in the chemical organizations obtained from this work. The stoichiometric and dynamical properties of those sub-networks merit further exploration. Pág. 9 – 18, esquemas, imágenes. Thu, 01 Dec 2022 00:00:00 GMT https://repositorio.utem.cl/handle/30081993/1378 2022-12-01T00:00:00Z https://repositorio.utem.cl/handle/30081993/1377 Modeling macroparasite infection dynamics. López, Gonzalo Maximiliano; Aparicio, Juan Pablo In this work we present a general framework for the modeling of the transmission dynamics of macroparasites which do not reproduce within the host like Ascaris lumbricoides, Trichuris trichiura, Necator americanus y Ancylostoma duodenale. The basic models are derived from general probabilistic models for the parasite density-dependent mating probability. Here we considered the particular, and common case, of a negative binomial distribution for the number of parasites in hosts. We find the basic reproductive number and we show that the system exhibits a saddle-node bifurcation at some value of the basic reproduction number. We also found the equilibria and basic reproduction number of a model for the more general case of heterogeneous host populations. Pág. 1 – 7, gráficos, fórmulas. Thu, 01 Dec 2022 00:00:00 GMT https://repositorio.utem.cl/handle/30081993/1377 2022-12-01T00:00:00Z