Abstract (Introduction): Within the framework of the present capitalist system, human beings have become an important polluting agent. Current production and consumption processes do not consider the existence of finite natural resources and a planet incapable of treating the waste that the prevailing way of life generates. Given these circumstances, the study of non-linear models is of interest, which make a more rational use of the waste that the productive activity generates, favoring recycling mechanisms. The phenomenon of recycling becomes particularly relevant in the case of electrical and electronic devices, whose ability to be degraded and metabolized by planet Earth is extremely difficult. (Objective): Evaluate the feasibility of installing and starting a recycling plant for electrical and electronics items in the town of Bahía Blanca (Argentina), during 2021. (Methodology): The conventional method for evaluating investment projects was used, considering technical, legal and economic aspects. (Results): The project is not acceptable according to the profitability intended by the investor. The possibility of financing was also included, which made the project even less profitable, and the sensitivity of the results was measured, finding that the price should be 1.48 % higher than that used in the analysis. (Conclusions): Other alternatives must be explored to make this proposal profitable from an economic and financial point of view.

Resumen (Introducción): En el marco del sistema capitalista vigente, el ser humano se ha transformado en un agente significativo de contaminación. Las dinámicas productivas y de consumo actuales no contemplan la existencia de recursos naturales finitos y de un planeta incapaz de procesar los desperdicios que el modo de vida habitual genera. Dadas estas circunstancias, cobra interés el estudio de modelos no lineales, que hagan un uso más racional de los residuos derivados de la actividad productiva, los cuales favorezcan mecanismos de reciclaje. El fenómeno del reciclaje se vuelve, en particular, relevante para el caso de los artefactos eléctricos y electrónicos; la capacidad del planeta Tierra para degradarlos y metabolizarlos resulta sumamente difícil. (Objetivo): Evaluar la factibilidad de la instalación y puesta en marcha de una planta recicladora de artículos eléctricos y electrónicos en la localidad de Bahía Blanca (Argentina), durante el 2021. (Metodología): Se utilizó la metodología convencional de evaluación de proyectos de inversión, considerando aspectos técnicos, legales y económicos. (Resultados): El proyecto no es aceptable según la rentabilidad pretendida por el inversor. También se incluyó la posibilidad de un financiamiento, lo que hizo que el plan fuera menos rentable aún, y se midió la sensibilidad de los resultados: se halló que el precio debiera ser 1.48 % superior al utilizado en el análisis. (Conclusiones): Se deben explorar otras alternativas para lograr que el proyecto sea rentable desde el punto de vista económico-financiero.

ABSTRACT: Vale do Rio Doce shoot dieback (VRDSD) is an anomaly whose cause seems to be associated with hypoxic conditions and their consequences (excess Mn and Fe) triggered by elevation of the water table in areas with poor drainage. Different plants have distinct survival strategies under this form of stress. The objective of this study was to understand the physiological responses involved in the differential tolerance of eucalyptus clones to VRDSD and their relationship to hypoxia and excess Mn. A hydroponic experiment was carried out using a 2 × 2 × 2 factorial arrangement, two eucalyptus clones with different levels of tolerance to VRDSD (sensitive Urograndis hybrid - 1213; and the tolerant Rio Claro hybrid - Eucalyptus grandis x unknown - 2719), two concentrations of O2 (8 and 4 mg L-1), and two Mn concentrations (1.39 and 300 mg L-1) in a randomized block design (RBD) with three replicates. Forty-day-old clones were maintained in Clark nutrient solution for 30 days. After this period, the treatments were applied for 11 days. Plant gaseous exchange shoot and root production, and the quantity of enzymes related to oxidative stress in leaves and roots were evaluated. In the tolerant clone, reactive oxygen species (ROS) were produced under hypoxic conditions, accompanied by reduction in production of dry matter, malondialdehyde (MDA), and in activity of the enzyme alcohol dehydrogenase (ADH). However, this clone had greater production of superoxide dismutase (SOD) under these conditions, an enzyme responsible for detoxification of ROS, which acts as part of the Low Oxygen Quiescence Syndrome (LOQS). In contrast, sensitive clones did not exhibit expressive reductions in growth or changes in the leaf/root ratio. These clones formed large quantities of adventitious roots and had high levels of MDA and ADH and low levels of SOD. Therefore, sensitive clones appear not to be prepared for detoxification of ROS and other toxic metabolites, but rather adopt morphological escape mechanisms, the Low Oxygen Escape Syndrome (LOES), in response to hypoxia. Thus, the period of soil waterlogging may cause the death of large numbers of roots in sensitive clones, limiting their ability to absorb water and nutrients and culminating in the death of these plants. Excess Mn seems to aggravate the damage caused by hypoxia, but it is not the causal agent of VRDSD.