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Electrokinetic soil remediation (EKR) is one of the most promising techniques for decontamination of low permeability soils, in which the most classical techniques have been found to be less efficient. However, its practical application on a real scale has been rather limited since the phenomena involved in these processes are very complex. For this reason, it is essential to use numerical models that allow us to know the main trends in the behaviour of soils and natural waters subjected to EKR processes. This study presents the numerical model M4EKR (Multiphysics for ElectroKinetic Remediation). The M4EKR module is a reactive transport model for partially saturated soils that allows reproducing the transport of species due to electroosmosis, electromigration, diffusion and advective flow. The model was completely implemented in COMSOL Multiphysics, a partial differential equation solver. The system of differential and algebraic equations to solve the chemical and transport problem was fully defined by the authors, and they were solved by the M4EKR module in COMSOL (monolithic approach). The scope of the model is illustrated by simulating an EKR process of a natural soil and porewater contaminated with a polar pesticide: 2,4-Dichlorophenoxyacetic acid. For simplicity, the M4EKR version used in this study does not include gas transport, it does not consider the deformability of the soil and it is assumed the processes occur under isothermal conditions.

The proposed use of active clays for the isolation of radioactive wastes in deep geological repositories has been followed by a deeper understanding of this type of soils. This increased knowledge has led to the need for both conceptual and numerical models capable of capturing the main trends in behaviour and the different couplings between different physical-chemical phenomena. In addition, the model must have a high degree of flexibility that enables it to accommodate future developments or new relevant phenomena. This work presents a numerical THMC code developed entirely on the COMSOL Multiphysics numerical implementation platform, which provides the required adaptability. This model includes, for the first time in this environment, a reactive transport model in unsaturated porous media for a relevant geochemical system (consistent with the MX-80 bentonite) together with a THM model based on a double porosity approach. The chemical potentials of water and solutes are used for the definition of thermodynamic equilibria between both porosity levels. Trends in the behaviour of a bentonite sample under oedometric conditions are satisfactorily simulated in response to a process of saturation and change in salinity conditions. Variations in swelling pressure, porosity distribution or dissolution/precipitation of the main accessory minerals are analysed and explained by means of the proposed conceptual model.

Myeloproliferative neoplasms are chronic disorders of clonal hematopoietic stem cells, characterized by an overproduction of functional granulocytes, red blood cells and / or platelets, and one of the major complications is the occurrence of venous and arterial thrombotic problems caused by increased platelet aggregation and thrombin generation. In this study 11 cases of primary myelofibrosis (PM) were evaluated and 2 debuted with splanchnic venous thrombosis (SVT); so after seeing the results of this study and of world literature, it is suggested that in patients with SVT, diagnostic methods for PM like the JAK2V617F mutation should be included., (Copyright: © 2017 SecretarÍa de Salud)