Renormalization: the observable-state model

The usual mathematical formalism of quantum field theory is non-rigorous because it contains divergences that can only be renormalized by non-rigorous mathematical methods. The purpose of this paper is to present a method of subtraction of this divergences using the formalism of decoherence. This is achieved by replacing the standard renormalization method by a projector on a well defined Hilbert subspace. In this way a list of problems of the standard formalism disappears while the physical results of QFT remains valid. From it own nature, this formalism can be used in non-renormalizable theories.Comment: 23 page

Phase transition-like behavior of the magnetosphere during substorms

The behavior of substorms as sudden transitions of the magnetosphere is studied using the Bargatze et al. [1985] data set of the solar wind induced electric field vBs and the auroral electrojet index AL. The data set is divided into three subsets representing different levels of activity, and they are studied using the singular spectrum analysis. The points representing the evolution of the magnetosphere in the subspace of the eigenvectors corresponding to the three largest eigenvalues can be approximated by two-dimensional manifolds with a relative deviation of 10-20%. For the first two subsets corresponding to small and medium activity levels the manifolds have a pleated structure typical of the cusp catastrophe. The dynamics of the magnetosphere near these pleated structures resembles the hysteresis phenomenon typical of first-order phase transitions. The reconstructed manifold is similar to the "temperature-pressure-density" diagrams of equilibrium phase transitions. The singular

General considerations, indications and contraindications for liver transplantation in Chile. A multicenter consensus development document Trasplante hepático en Chile: Aspectos generales, indicaciones y contraindicaciones (Documento de consenso)

Liver transplantation is an excellent therapeutic option for terminal liver disease. During the last decades the results of liver transplantation have improved significantly with a patient survival rate of nearly 90% at one year and 80% at 5 years of follow-up. The main indications for liver transplantation include: end-stage liver disease associated to cirrhosis, acute liver failure, and hepatic tumors (mainly hepatocarcinoma). The absolute contraindications for a transplant are less frequent than in the past, and include: severe co-morbidity (cardiac or pulmonary), sepsis, advanced HIV disease and extra-hepatic malignancy. This document presents a Consensus of the main groups performing liver transplantation in Chile, about its indications and contraindications. It also reviews general aspects of liver transplantation, including the selection and referral of liver transplant candidates, allocation of organs and the evaluation of severity of liver disease