I missed the publication of this last month. The abstract :
The major insight in Robert Rosen’s view of a living organism as an (M,R)-system was the realization that an organism must be “closed to efficient causation”, which means that the catalysts needed for its operation must be generated internally. This aspect is not controversial, but there has been confusion and misunderstanding about the logic Rosen used to achieve this closure. In addition, his corollary that an organism is not a mechanism and cannot have simulable models has led to much argument, most of it mathematical in nature and difficult to appreciate. Here we examine some of the mathematical arguments and clarify the conditions for closure.
This is a wide-ranging paper which seeks to illuminate and clarify “closed to efficient causation” and its consequences. In the relatively short space of 14 pages, the authors manage not only to delve into some of the mathematical aspects of “closed to efficient causation”, but also counter the arguments of a number of previous critics who had erroneously claimed that “closed to efficient causation” models are simulable.
 Cárdenas,M.L., Letelier,J.-C., Gutierrez,C., Cornish-Bowden,A., Soto-Andrade,J. 2010. “Closure to efficient causation, computability and artificial life”. J. of Theoretical Biology. 263(1):79-92. DOI:10.1016/j.jtbi.2009.11.010.