Multistability and complex basins in a nonlinear duopoly with price competition and relative profit delegation.

In this article, we investigate the local and global dynamics of a nonlinear duopoly model with price-setting firms and managerial delegation contracts (relative profits). Our study aims at clarifying the effects of the interaction between the degree of product differentiation and the weight of manager's bonus on long-term outcomes in two different states: managers behave more aggressively with the rival (competition) under product complementarity and less aggressively with the rival (cooperation) under product substitutability. We combine analytical tools and numerical techniques to reach interesting results such as synchronisation and on-off intermittency of the state variables (in the case of homogeneous attitude of managers) and the existence of chaotic attractors, complex basins of attraction, and multistability (in the case of heterogeneous attitudes of managers).

Asset price and wealth dynamics as an adaptive belief system.

In this paper we study an asset pricing model with heterogeneous beliefs, wealth dynamics and time varying proportions. We derive the resulting deterministic nonlinear dynamic system and analyze the model with adaptive beliefs and switching mechanism in order to investigate bifurcations and global dynamics and thus consider the effects on wealth distribution among different types of agents. Our study aims at confirming that heterogeneity in beliefs may lead to complexity.

Atrial natriuretic peptide in diabetic and nondiabetic patients with and without heart transplantation.

Background: Natriuretic peptides are useful markers for risk stratification of patients with heart disease. However, conflicting results have been reported about circulating atrial natriuretic peptide (ANP) concentration in heart transplant recipients.

Methods: To ascertain the effects of diabetes and acute insulin administration on plasma ANP concentrations in a model of heart denervation, we studied 12 diabetic (D-OHT) and 6 nondiabetic heart-transplanted (OHT) patients using the euglycemic-hyperinsulinemic clamp and oral glucose tolerance tests.

Evaluation of cytomegalovirus DNAaemia versus pp65-antigenaemia cutoff for guiding preemptive therapy in transplant recipients: a randomized study.

Methods: A bicentre, randomized, prospective open-label study aimed at defining a DNAaemia versus antigenaemia cutoff for guiding preemptive therapy of human cytomegalovirus (HCMV) infections in solid organ transplant recipients (SOTR) was completed. Overall, 99 patients were enrolled in the DNAaemia arm and 101 patients in the antigenaemia arm. Patients were randomized to be monitored for HCMV infection in the blood by either assay.

Treatment of refractory heart failure with a percutaneous circulatory support device.

End-stage heart failure refractory to medical therapy is a clinical challenge. Heart transplantation is considered the best strategy, but it remains burdened with substantial limitations due to the scanty availability of facilities with a transplant programme, donor shortage, and unpredictable waiting lists. Alternatively, assist devices may allow an improvement of the haemodynamic conditions, modifying the history of end-stage heart failure and introducing new management strategies.