Epigenetic Tracking: Implementation Details

"Epigenetic Tracking" is the name of a model of cellular development that, coupled with an evolutionary technique, becomes an evo-devo (or "artificial embryology", or "computational development") method to generate 2d or 3d sets of artificial cells arbitrarily shaped. 'In silico' experiments have proved the effectiveness of the method in devo-evolving any kind of shape, of any complexity (in terms of number of cells, number of colours, etc.); being shape complexity a metaphor for organismal complexity, such simulations established its potential to generate the complexity typical of biological systems. Moreover, it has also been shown how the underlying model of cellular development is able to produce the artificial version of key biological phenomena such as embryogenesis, the presence of "junk DNA", the phenomenon of ageing and the process of carcinogenesis. The objective of this document is not to provide new material (most of the material presented here has already been published elsewhere): rather, it is to provide all details that, for lack of space, could not be provided in the published papers and in particular to give all technical details necessary to re-implement the method.Comment: 26 pages, 20 figure

Exact design solutions for photodiode transimpedance amplifiers based on FET input OP-AMPs

We calculate the transfer function of an optical receiver composed by a photodiode and a FET input operational amplifier as a current to voltage converter. According to the theory of low-pass filters, the receiver bandwidth and quality factor are here analytically evaluated, proposing design solutions and their related sensitivity to eventual parameter fluctuations. We exemplify the combined action of photodetection and filtering comparing the analytical expression with full numerical SPICE simulations

Evolution and development of complex computational systems using the paradigm of metabolic computing in Epigenetic Tracking

Epigenetic Tracking (ET) is an Artificial Embryology system which allows for the evolution and development of large complex structures built from artificial cells. In terms of the number of cells, the complexity of the bodies generated with ET is comparable with the complexity of biological organisms. We have previously used ET to simulate the growth of multicellular bodies with arbitrary 3-dimensional shapes which perform computation using the paradigm of "metabolic computing". In this paper we investigate the memory capacity of such computational structures and analyse the trade-off between shape and computation. We now plan to build on these foundations to create a biologically-inspired model in which the encoding of the phenotype is efficient (in terms of the compactness of the genome) and evolvable in tasks involving non-trivial computation, robust to damage and capable of self-maintenance and self-repair.Comment: In Proceedings Wivace 2013, arXiv:1309.712

An analysis of euro area sovereign CDS and their relation with government bonds

This paper studies the relative pricing of euro area sovereign CDS and the underlying government bonds. Our sample comprises weekly CDS and bond spreads of ten euro area countries for the period from January 2006 to June 2010. We first compare the determinants of CDS spreads and bond spreads and test how the crisis has affected market pricing. Then we analyse the ‘basis’ between CDS spreads and bond spreads and which factors drive pricing differences between the two markets. Our first main finding is that the recent repricing of sovereign credit risk in the CDS market seems mostly due to common factors. Second, since September 2008, CDS spreads have on average exceeded bond spreads, which may have been due to ‘flight to liquidity’ effects and limits to arbitrage. Third, since September 2008, market integration for bonds and CDS varies across countries: In half of the sample countries, price discovery takes place in the CDS market and in the other half, price discovery is observed in the bond market. JEL Classification: G00, G01CDS, Credit Spread, financial crisis, Government bond, limits to arbitrage