Emergent complex neural dynamics

A large repertoire of spatiotemporal activity patterns in the brain is the basis for adaptive behaviour. Understanding the mechanism by which the brain's hundred billion neurons and hundred trillion synapses manage to produce such a range of cortical configurations in a flexible manner remains a fundamental problem in neuroscience. One plausible solution is the involvement of universal mechanisms of emergent complex phenomena evident in dynamical systems poised near a critical point of a second-order phase transition. We review recent theoretical and empirical results supporting the notion that the brain is naturally poised near criticality, as well as its implications for better understanding of the brain

Life Span of Silicone Gel-Filled Mammary Prostheses

The discussion on possible side effects of implanted silicone has resulted in a growing number of patients inquiring whether or not their mammary prostheses are intact and when failure of the prostheses is to be expected. Between November 1988 and May 1995, 182 patients had their silicone mammary prostheses replaced, repositioned, or removed one to three times. Capsular contraction, dislocation, pain paresthesia, and/or suspected rupture were common indications for surgery. To try and be able to provide an indication as to the correlation of implant age and integrity, we recorded the status of all 426 prostheses observed during secondary surgery. In this selected group of patients, approximately 50 percent of the mammary prostheses with an implant age of 7 to 10 years showed gel bleed or rupture. Applying the survival Kaplan-Meier curve, 50 percent of implants may be expected to bleed or be ruptured at the age of 15 years. Rupture was observed more frequently than gel bleed. It seems that there is no chronologic relation between gel bleed and rupture

Genome-wide association study identifies novel genetic variants contributing to variation in blood metabolite levels

Metabolites are small molecules involved in cellular metabolism, which can be detected in biological samples using metabolomic techniques. Here we present the results of genome-wide association and meta-analyses for variation in the blood serum levels of 129 metabolites as measured by the Biocrates metabolomic platf