The Genus Phragmatobia in North America, with the Description of a New Species (Lepidoptera: Arctiidae)

Excerpt: This paper, based on the examination of 1,879 specimens, serves to resolve the taxonomic problems involving the three North American species of Phragmatobia. The genus Phragmatobia, the ruby tiger moths, has had a checkered history since it was described by Stephens in 1829 (type, by monotypy, Noctua j\u27uliginosa Linnaeus, 1758). Although many species have been described in or transferred to this genus, in both the Old and New Worlds, most of them have been removed to other genera. By 1902 Dyar recognized only two North American species, a status since then unchanged (McDunnough, 1938; Forbes, 1960). Despite the recent stability of the names, there has been much confusion as to which names to apply to particular specimens. This problem is resolved below, with the description of a third North American species, long confused with the two named species

Synchronisation in random dynamical systems

In this thesis, we develop a deeper and much more extensive theory of synchronisation of trajectories of random dynamical systems (RDS) than currently exists. In particular, focusing on random dynamical systems with memoryless noise, we achieve two main goals: Firstly, we demonstrate that the notion of "statistical equilibria" is purely a property of the measurable dynamics of a RDS on a standard Borel space; and yet, within such statistical equilibria is "encoded" the phenomenon of noise-induced synchronisation (which may then be observed in *any* compatible metric on the phase space). Secondly, we provide new, widely applicable criteria for synchronisation in RDS, considerably improving upon some of the existing criteria for synchronisation.Open Acces

Buffered Qualitative Stability explains the robustness and evolvability of transcriptional networks

The gene regulatory network (GRN) is the central decision‐making module of the cell. We have developed a theory called Buffered Qualitative Stability (BQS) based on the hypothesis that GRNs are organised so that they remain robust in the face of unpredictable environmental and evolutionary changes. BQS makes strong and diverse predictions about the network features that allow stable responses under arbitrary perturbations, including the random addition of new connections. We show that the GRNs of E. coli, M. tuberculosis, P. aeruginosa, yeast, mouse, and human all verify the predictions of BQS. BQS explains many of the small- and large‐scale properties of GRNs, provides conditions for evolvable robustness, and highlights general features of transcriptional response. BQS is severely compromised in a human cancer cell line, suggesting that loss of BQS might underlie the phenotypic plasticity of cancer cells, and highlighting a possible sequence of GRN alterations concomitant with cancer initiation. DOI: http://dx.doi.org/10.7554/eLife.02863.00

Object Database Scalability for Scientific Workloads

We describe the PetaByte-scale computing challenges posed by the next generation of particle physics experiments, due to start operation in 2005. The computing models adopted by the experiments call for systems capable of handling sustained data acquisition rates of at least 100 MBytes/second into an Object Database, which will have to handle several PetaBytes of accumulated data per year. The systems will be used to schedule CPU intensive reconstruction and analysis tasks on the highly complex physics Object data which need then be served to clients located at universities and laboratories worldwide. We report on measurements with a prototype system that makes use of a 256 CPU HP Exemplar X Class machine running the Objectivity/DB database. Our results show excellent scalability for up to 240 simultaneous database clients, and aggregate I/O rates exceeding 150 Mbytes/second, indicating the viability of the computing models

Data quality implications of scientific software complexity

Scientific findings based on computer simulation evoke sceptical responses because their output does not appear to have an objective status comparable to data captured by observation or experiment. However the simulationists have been defended on grounds that their practices, like those of experimenters, carry with them their own credentials. It has been further argued that epistemic opacity is essential to the nature of computational science and that epistemology of science must cease to be anthropocentric. Such philosophical faith in software runs counter to both established practice in software engineering, and the underlying software engineering science. In computational science as elsewhere data quality can only be assured through the exercise of human critical judgment